We really need to find out exactly what made walt leave her on the altar. I feel like that's gonna be one of the show's last key revelations, and I'd be willing to bet money it'll be in a flashback in the cold open of the last episode.
He left her on a vacation to Newport (possibly to her house, maybe not, it's ultimately irrelevant) with her father and brothers, not the altar (they were in a relationship though).
For this kind of analysis to hold up, you basically have to assume that Walt was always a "bad guy", even in the early seasons. But if he was always bad, then there's no descent. It seems much more logical that Walt did (and still does) have a fair amount of human empathy, compassion, loyalty, etc.
Edit: I mean obviously there were always elements of badness in him (as there are in all of us). What I mean is that your analysis makes him a completely unsympathetic character very early in the story.
Full disclosure, I strongly believe Walter was always a 'bad guy' and have done so for quite awhile. I don't see how the lack of a descent or sympathy makes him less compelling and interesting though.
Anyway, if we look at it chronologically (also the Gray Matters section I'm taking from a post I made awhile ago since it's easier than writing it all out again):
JOB HISTORY
Elliott and Walter as partners. [Gray Matters]
-Gretchen as Walter's former love.[I cannot recall the precise episode but I'm highly confident it has been strongly suggested, I believe it was at the end of Gray Matters]
-Elliott being married to Gretchen. [Gray Matters]
-Walter leaving suddenly from the fourth of July vacation (where he was with Gretchen's family), barely saying a word. [Peekaboo]
-The reason for it not being understood by others and it being clear that Walter was the one who left, not being forced out or knowlingly slighted ("You left me", "You walked away", "You abandoned us", "barely talking"); this also suggests it was seen as illogical since it wasn't properly understood which alligns with why Gretchen and Elliott do not have a problem paying for the treatment (if it was a large argument they would certainly be much more hesitant or there would be some tension between them whereas all tension seems to stem from Walter). [See Peekaboo]
-Walter's incredible capacity to spite others, particularly for perceived betrayals [See Green Light].
-Gretchen citing that Walter abandoned her and Elliott which fits in with Walter's ego by thinking that he was an irreplaceable part of the company and without him it would fail (which he also did with Jesse in season three to a lesser extent while also being something that he later did with the Fring organisation and coincidentally conforming with why he didn't have a problem taking the buyout at the time). [See Peekaboo, Green Light, Cornered]
-Walter's magnificent ability to lie (to himself and others) and frame himself as a victim (which makes his side of the story nowhere nearly as credible as Gretchen's; there's little reason to doubt her given what we have seen of her in the show). [See everything regarding his "for my family" excuse and for the latter part his manipulation of Jesse, Marie, Walter Junior, Hank Gretchen]
-Walter's obsessive need for control and dominance. [The series; see his relationship with Skyler, Gus, Jesse, Mike, Saul, pretty much everyone]
-Gretchen's status at the creation of Gray Matters being 'higher' than Walter's ('rich girl just adding to her millions' which is something he very clearly dislikes given the delivery and phrasing of this line). [Peekaboo]
-Walter's speech in Bug about his father clearly indicating that his issues of power, pride and dominance are deep-seated (although it was clear beforehand, this more-or-less outright states it)
-Walter as a manipulator in his meeting of Skyler which long precedes the show. [Cancer Man]
While we do not know the exact specifics (whether he left over Gretchen and Elliott or if it was to do with Gretchen being of a higher class which Walter resented by making him feel as if he did not have as much control as she would have had given her wealth; the latter seems much more likely than the former because no bridges were burnt and the reason for Walter leaving was inexplicable to the others), everything we do know about Walter and the incident suggests it was of Walter's own creation as a result of his character traits (primarily his pride and ego). There isn't anything to suggest it is anything other than his own fault. The only reason one would necessarily believe anything else is by siding with Walter's account in Peekaboo which seems illogical considering that we have ample reason to distrust Walter (his delusion and lying) and no reason to distrust Gretchen.
Next, he worked in Application Labs (Cancer Man). We know nothing other than that it was clearly not successful. He worked in a chemical lab when he met Skyler (Cancer Man) and that too wasn't successful and he also worked in Sandia Laboratories (Full Measures), also not successful.
At this point, before the show begins, we know one thing of Walter, that he is a man unable to properly hold down jobs who had multiple opportunities to work in (or in one case, jointly own) a large company. One or two I could concur that he was unlucky, but four? It's possible, but look at the job he ultimately ends up with, a high school teaching position, a job where he is in a position of power over those he works with (his students of course, not the staff). In looking at personality disorders, an inability to maintain a job for a considerable length of time is often something that is considered (among many other things of course) to see the impact it has had on somebody's life. Now, you could say 'but I've had fifteen jobs, I'm hardly a psychopath/sociopath/suffering from Antisocial Personality Disorder' and true, but the show isn't reality, it's a crafted tale and information is included if it's deemed pertinent by the writers. Take Hank, Marie and Skyler for example; Hank's had two mentioned jobs (one for college/his youth and the other as a DEA agent, presumably for a loong time), Marie is a nurse (no mention of anything else that I recall), Skyler is an accountant (who voluntarily left Beneke's) and is a failed novelist. Only Walter has received an indication of an inability to properly secure/maintain a job prior to the show (and as mentioned, the one he does have puts him in a position of power).
The job at the car wash (not included in the 'big jobs' obviously) broke down when he was ordered to do something (this was after the diagnosis so I can accept that it was a reaction to that). And the job at the school? He couldn't maintain that either (of course, as we recall it was for overtly flirting with Carmen as a way to seek vengeance for Skyler's relationship with Ted so maybe it's not worth mentioning).
In total, the job's Walter has had are: Gray Matters, Application Labs, Chemical Company, Sandias Laboratories, School Teacher, Car Wash, Six jobs, four pottentially large jobs, one part time job. If we include his drug dealings, you can include a supplier to Tuco, a supplier to Gus, a supplier to Dennis/Lydia but I'll avoid doing this since they could, perhaps, be argued against as self preservation (I will get to them later).
RELATIONSHIPS
His relationship with his father was nearly non-existant (only in that he died when he was six and Walter has only one image of his father) and his memory of his father is of a weak man dependant on others, lacking any form of control (lacking control of his body and something that Walter himself utterly feared and was revolted at.
His relationship with his mother is clearly poor but we don't know much more.
For Gretchen see Gray Matters since they're intertwined but Walter ended it out of pride.
Skyler's relationship began with Walter manipulating her to speak to him.
No other close friends are mentioned but this is likely for casting and plotting reasons.
During the show:
His gut reaction to being trapped is to commit suicide by police officer as he points his gun at the oncoming sirens; this is not a moral thing to do. If he had killed himself? Fine, but to do so by shooting at others?
He decided to start selling crystal meth. Ignore Walter's deluded.cries that it's for his family, he decided to sell an awful drug that ruins many peoples lives and puts his family in perilous danger. If we assume his intent was to help his family (which could be seen as good***), there is not a single place in the entire universe where this should be seen as anything other than an immoral, reprehensible choice.
He continuously lies to Skyler for three weeks (and this is solely the pilot). Yes he is in a slightly submissive position to her but...so what? What difference does that make? If Walter was dominant and Skyler was submissive would Walter somehow be bad and Skyler good? The power dynamic is within the realms of that of a pretty normal relationship, not a thriving one, but a normal, bland relationship.
He murdered a man. This could be self defense but I'll comment on that aspect later. He changes his '50/50 partners' to 'I am the one in control, go buy what I tell you to buy'.
He immediately puts himself in a position of power over Jesse. Yes he's more competant at this, but he establishes dominance. Note how Jesse continuously calls Walter 'Mr. White' (this occurs throughout the series), a reminder of the power Walter has over Jesse. Yes he also does not turn Jesse in, but he blackmails him into working for him, something that has far worse ramifications. Walter's very first interaction with Jesse is to manipulate him and use him.
He murders a second man. Now, this is where the self defense aspect and family danger comes into play. The moral thing to do would be to go to the police as he is alive. Now, I can understand that this would be bad for Walter so let's say that that was not an option (even though in truth, it is a valid option). Walter was, at this point, immediately aware of the danger his family was in. Just look at the notes he has on the murder of Krazy 8, the negative to releasing him is that he'll murder his entire family. Walter, from this point, immediately knew his family was in grave danger. While he would be a bad person, I could somewhat understand the previous decisions if, at this point, he decided he was done and that was the end, but any delusions he may have had about the drug business putting their lives at risk and being bad for them is gone at this point. He continues knowing full well the threat they are under. He also takes sandwiches without the crust as he did.
He blows up a man who annoys him's car. He was empowered by his experience. This is not how a normal man would behave.
***Now, this is the big one. Gray Matters. At this point, Walter's 'for my family' excuse is gone. If his intent was purely to provide for his family, he takes the deal, either deal. There is something more, his pride, ego, and sense of control. He has already been (as stated) empowered by his experience. He is fully aware of the danger his family is in, and he's fully aware of what things he will have to do in the busness.'But that wouldn't leave money for his child's tuition'! Perhaps not, but look at the valuation of Gray Matters. Neither Gretchen or Elliott harbour ill-will towards Walter, it's solely on his end; maybe they wouldn't pay for it or pay him more, but he never even asked. Also note how they offered a six figure salary with medical care. Walter wouldn't have had to spend a dime on medical bills and all he needed (which he decided later) was '737,000'. We don't know the exact offered salary, but given how essential Walter was in Gray Matter's formation I could absolutely buy that he would have achieved that. But no, he returns to cook meth instead. If many prideful people would do that, many prideful people are self-absorbed. That is not logical, it is not rational, and it is not moral. We know from later on in the show just how good Walter is at lying to himself. Regardless of what his intent was up to this exact moment, this is where he begins lying to himself. If you look at it in any logical manner, Walter is not doing it for his family from this point forward, regardless of what he has convinced himself. Take note how he doesn't even care about others seeing him as dependant/accepting charity as he actually goes so far as to tell Skyler that he accepted.
Walter gets Jesse to be the public face (Jesse absolutely should have walked away right here but he absolutely needs some form of approval that he's never before had). Yes this is mostly about protecting his own identity but he does it by putting Jesse's at extreme risk. '50/50 partners', they should share the risk, regardless of th division of labour (which Walter intrudes upon; the initial meeting with Tuco to retrieve the money I can understand, but he then makes a deal with Tuco and also asserts his dominance over Tuco making him take more out of greed).
He continues belittling Jesse in the open house.
Still lying to Skyler, there's also the attempted rape to put himself in a position of power over her. There is the fear that he has placed upon his entire family through his disappearance.
The danger to his family is once again noted as Tuco reminds him there's lots of collateral when dealing with a family man. If he had any delusions up to this point, this is where he should leave. He also takes Jesse's gun from him (once again asserting his power over Jesse) by arguing that he needs it more (and while that maybe true, it also means he's removing Jesse's form of defense).
I could continue in this detail but I'm unsure if you'd read it so let me hit on the main points:
He burns his bridges with Gretchen and Gray Matters (who were still willing to pay for the treatment). This is the point where Walter being a sociopath who was bound by fear (note that this is directly stated in the show 'until my diagnosis I couldn't sleep everynight due to my fear. Since then, I've slept soundly ever since.' to paraphrase, but I know it's said to Hank [I believe sometime after Negro y Azul]) because it is here where we get our insight into his past.
He continues manipulating and belittling Jesse while getting him to continue in the drug business. If Walter cared for Jesse, he would not tell him to go murder Splooge and skank (I know that's not her name), I would not tell somebody I care about to go murder somebody else. Jesse has already proven himself completely unable to handle the dark things that they are doing (which Walter has no few apparent qualms about as he's put two murders behind him already [let's not forget that he intended to leave Tuco for dead]). He barely even notices it or acknowledges this. He continues to make Jesse the public figure andwhich exposes him to risk and Walter, time and again, intrudes upon Jesse's side of business to control him. The handling of breakage for example should be Jesse's decision but Walter intrudes. Deciding to expand should be Jesse's decision, Walter intrudes. Walter needs Jesse, but cares about him? He may think he cares about him, but he cares about him in an entirely self-centered manner (this will continue to be argued in Jesse parts).
The lack of sensitivity (or interest) he displalys concerning Combo's death. He shows no interest or concern in how Jesse is feeling and doesn't display even the slightest bit of regret.
The murdering of Jane. Yes, not initially intended as Walter shook Jesse which knocked Jane onto her back which allowed her to drown in her vomit but no event highlights his lack of care for Jesse as much as this (in the early stages of the show). Not only is the act itself abhorrent, but the emotional destruction that any person should have seen it would cause on Jesse is almost as bad. Before you argue 'both would have died', 'she deserved it', 'he cared about Jesse in tht instance', let me intrude by saying, no, just no. The way to handle the situation was precisely what Donald was going to do (which is what a normal human would have done), call the police about potential drug use, take the money (so it isn't seized), get them to go to rehab and return the money afterwards. There were ways to handle the situation that did not evolve murdering the woman Jesse loved and leaving him with a crushing feeling of guilt. There is an aspect of self preservation in the murdering of Jane but this is not an excuse. Somebody can be cold and calculated. Somebody can do moral things. Sometimes.these overlap, but in this instance, they don't. It was immoral and wrong to let Jane die, regardless of how much it benefitted Walter (it also benefitted Walter for Jane to be out of the way so Jesse was entirely reliant upon him). Walter does have a paternal relationship with Jesse, but it's extremely twisted and warped; it's not a healthy relationship for Jesse and it only benefits Walter (at the expense of Jesse), Jesse has gotten nothing out of it other than some small moments of gratitude. On the money aspect though, it isn't really his to take. Jesse is his own person and if that was Jesse's decision, it was his decision to make. Walter should not have complete control over Jesse's life. If we accept that Jesse would have died otherwise, it would have been bad, sure, but Jesse would have died with at least one thing he loved in his life, he wouldn't have continued to be Walter's pawn to be emotionally manipulated at every stage and crushed by guilt.
Continues to lie to Skyler who decides to leave. Walter's denial and delusions become even more apparent, particularly with the plane crash.
Continuously insults Jesse as he makes his own meth, denies that Jesse has any competency, asserts that he is solely in control, denies there's any partnership (paraphrased 'it's mine' in relation to their product when, as Jesse rightly says, it's theirs as per their agreement) and reveals what he actually thinks of them and Jesse together.
He refuses to sign the divorce papers (initially) to assert his dominance over her but also out of pure selfishness. His wife is clearly distraught, with no desire to be with him, yet he won't sign the divorce papers because he likes the idea of still being part of the family, despite the fact he's already partly ruined the family.
He praises Jesse only as a last resort to get him to join him in the superlab. I think this is one of the very few moments in the show where Walter says anything positive to Jesse, certainly one of the few moments where he's given any validation from Walter (whereas Mike and Gustavo both later praise him when appropriate).
-slight break here. I know I'm bringing up a lot of Jesse but that's because Walter's interactions with him and Skyler give the greatest credence to the claim that Walter was always a sociopath/has ASPD and I don't want the post to be far too long (although I think it already is)-
Still lying about motive. Note how he continuously states that he wants to be the provider. He wants to be in control so that his family are dependant and reliant upon him (of course he certainly wouldn't see it that way himself, or at least acknowledge it)
Now skipping a few to the Half Measures incident since I know this is brought up repeatedly. Yes, Walter murders the dealers to save Jesse. Walter does care about Jesse, but he cares about him in a selfish manner. Walter takes trophies from those he kills (sanwiches, drinks, children, car, Leaves of Grass, goatee [ok ignore this part of the sentence if you disagree, it's ultimately dispensible]), but he cares about him as his living trophy, a monument to his power Jesse is the two trunkless legs of stone which stand in the desert near the shatter'd visage which begs upon others to despair at Walter's mastercraft. Go back through any Jesse moment. When, at all, does Walter show concern for Jesse in a way that is not somehow involved in his continued manipulation of Jesse? The hug when Jesse is in the heroin den when Jesse breaks down is essential to getting him out of there. The murdering of Jane crushes Jesse with guilt. He never gives him praise and the one time he does is to manipulate him. He thinks of Jesse as a son, true, and he treats him like a pawn to be used (interestingly, Walter uses Junior as a pawn to be used in his power struggle with Skyler). Walter needs Jesse 'because he does what [Walter] tell
him to do' (as he said to Gus in explaining why he needs Jesse) and because Jesse is a man utterly dependant upon Walter (as he seeks some form of approval and love). Walter may view it as care, but it is need, an obsessive, compulsive and selfish need. Up to this moment, Walter never does anything solely for Jesse's benefit, he always does things for Jesse when he somehow gains from it, Look also at how Jesse mentions the 'three months' and Walter shrugs him off as being nonsensical when Walter himself has begun thinking of it. Jesse's concern was justified, and Walter acted as if he was a fool. Even if we say that yes, this was a selfless (immoral) act Water immediately asks for a reprisal for (that being the murder of Gale, murder being something Jesse has been adamantly against up until this point). The relationship between himself and Jesse has always centered around Walter's power and control; any time Jesse has sought a relationship with others (Mike for example) Walter has looked on with contempt and tried to manipulate him against them (Gus, Mike's hazard pay). There is an attachment, but not one that could be described as care from anybody's perspective but Walter's own.
Walter does not flinch at the murders.
Walter begins using children (mainly Junior though) as a wedge between himself and Skyler and to make his children side more with him than her. Note how this also occurs after the two dealers are murdered.
-from here most would argue he's a sociopath so just a few more-
Bogdan's sentimental dollar which he takes and uses because Bogdan appeared to be talking down to him.
His use of the cleaners.
He poisoned a child Jesse cared strongly about (risking his death; Lily of the Valley can be fatal so yes, Walter didn't intend to kill him, but he found it an acceptable risk), furthering his emotional manipulation of Jesse (and also scorning him after Gus left the car unused).
His continued behaviour with Skyler and framing her as the wrong one to relatives.
Bombs a nursing home. The fact that it's one room is hardly relevant, he planted a bomb in a nursing home. He also brought it into the hospital, to the pediatric care unit I might add. This was not necessary to his survival. What does Jesse do? He urges him to go to the DEA, to seek witness protection for himself and his family. Even if, somehow, he was some rational man who somehow managed to stay involved as long as he has, that is what you should do, not engage in quite a convoluted, risky strategy (that is an extreme long shot) to murder somebody with far more power than you have who is far more dangerous and well-equipped. He also gets a Volvo like Gus (in the flash-forward).
Pure manipulation to Jesse regarding the ricin cigarette
.