What did she say? If you want help judging whether you overreacted or she was actually insulting you, it'd be helpful info.
It's harsh to say, but you're a nice enough guy that they get the attention and recognition they seek, but you're not interesting enough to do these kinds of things with.
That's because they like the attention, but aren't interested in you. It's plainly not a nice thing to do, but people with insecurities will do these kind of things. Instead of ignoring, which is basically just pouting, you need to be firm. You need to tell them that you don't appreciate the way they treat you. Tell them you wouldn't mind going for a drink with them, but the way they keep flaking, tell them to not bother you unless they have time to not flake.
It may feel iffy being stern with girls, but it is what you're lacking. Being the nice guy that's always there may seem morally right and objectively like what you should do. But it doesn't create attraction. Even in that case, you need to think about yourself. If you want them as only friends, you then have the ability to say "I think it's rude to flake on plans you have with a friend". If you don't ask for anything, you won't get much.
The friend I have who is the best friend I know, and I mean the one that's best at being a friend, despite not being my best friend, is very much like this. He used to have a lot of people over during weekends, before they all went out. If someone behaved inappropriately, he'd say "either you change the way you are, right now, or I'm going to throw you out of my home". It's very fair, but also stern. The fact that it's fair means people will understand the sentiment. The fact that you're stern, combined with generally being a great guy, like this guy is, shows that he'll be a great friend so long as you treat him with respect. I cannot see a reason to settle for any less.
He did this to me, once, too. I flaked on some plans, and he told me it upset him. He had turned down someone else who asked if they should hang to hang with me. I felt bad for flaking on him, and understood his sentiment perfectly. It just showed that you expect some respect.
Be the same way with girls. You're not a doormat. You're a great guy that deserves to be treated without getting mixed signals. Don't bother about what creates the mixed signals, just tell them straight up that you don't appreciate being given mixed signals. If you also do tell them off and say that there's no point in contacting you unless they do wish to hang, you'll either have these ungrateful people out of your life, or, more likely, they'll contact you and suggest it themselves, next time.
You need to get a streak of edge going for you. I was hanging with a girl some days ago, and she just took a sip of my drink. I said that that was very rude and asked if they didn't have manners where she came from. It was kind of playful, but at the same time, she understood that I meant it. When she later tried to go for a sip, I took the glass away from her and said "nope, you're going to have to ask nicely." She did some uncontrite "can I PLEAASE have some?" and I said "no, you have to be contrite and sincere". It just shows that I'm not just another guy she can steamroll, as it seems she's used to facing.
This has nothing to do with 'being a bad boy', but more that you dare admit you're looking out for yourself. Sure, we like being there for others, but as I just said we like it. I'm there for others because I think it's interesting trying to help them out in troubled situations and understand what's going on, much like the reason why I'm in this thread. So I think it's fun. Trying to play it off as some altruistic and that I do this to be nice is kind of short-sighted. It's just that when we admit that it's ultimately for ourselves that we do many things, we can also see that we like being there for girls because we feel it might get us somewhere when we show how nice we are. But if you think that you should just do that and then they will simply love you, you're being short-sighted. You're already doing this for yourself, so why not also lay down some ground-rules that you won't be steamrolled by girls that try to steal your attention while they need it. Or your drink? Or anything that they really should treat with more respect? Why not demand that back.
That's often what people mean when they say 'stop being a nice guy', but they also wrongly pair it with 'girls like bad boys'. They do, because "bad boys" have those things that challenge them. They might not mind saying straight out they think they're being silly. So disregard the "bad boy" crap, and rather be stern with yourself and with girls. Lest you want to be a doormat. I could respect that. But then one shan't complain. Or something. I'm sure you'll figure it out.
The 'wait and see' approach is problematic, too, because you are her tossing-ball now. She knows you're there. Not to say that there isn't mutual attraction, it's just the fact that she has the upper hand, and can feel that.
No matter what, it's important that you show her that you're not about to be bullshitted. You're not there to comfort her when she's away from her boyfriend. You need to show her that if she just takes her sweet time, she'll risk losing you. That's what I did in the similar situation with my ex. She introduced me to some friends, and I really got a long with them. I put on a more flirty approach to one of them, and we had some good fun. That threw my ex for a bit of a loop, because she hadn't considered the fact that I was a great catch that more girls would be interested in. I don't remember if I wrote this or ended up not in my last post, but doing this was so powerful, that my ex even imagined seeing us doing footsies under a table later in the evening. She was basically devastated, because she suddenly felt she could lose me to another girl. She sent me a document where she poured her heart out, and said "I just have to say this, and maybe it'll work, maybe it won't". That essentially moved everything forwards, but the forcing of her hand was what was poignant.
This is basically just you being more assertive in the way things are moving. If you can indirectly show her that you're not just gonna hang around forever, that'd be good. Another thing that would be great would be if you said something like "given the circumstances, I don't think we should be hanging out during spring break". That has you saying that you're not comfortable being romantic with someone in a relationship, while it'll force her hand, because it shows that you've been there so far, but that now, you're no longer comfortable.
The problem with doing this is that it'll increase the chance of her picking in your favor. "Oh, that sounds great!" you say, but the thing is that you withdrawing will create an attraction and desire to be with you. This goes back to the fact that I can guarantee that the old boyfriend would be a problem. But at the same time, if you don't do this, she'll have the upper hand, and you'll be at huge risk of the same thing happening with you, in the future.
A transition like this demands reflection, which sadly seems lacking. There are tons of traps with such a relationship. At any rate, start focusing more on yourself. Be fair but stern. If you're not comfortable with the way she treats you, you should let her know. If you allow her to treat you in a way that thwarts your feeling of wanting to attempt to build something more, she's misusing you. Just look out for yourself.
You need to distance yourself. Being late twice should be no grounds to break up. If the workplace rumors were too much, that's a shame, but some people do value their career a lot, and if you were in the beginning of something, then I could definitely see that as a rational course of action. It seems the tardiness was just underlining what she was already feeling; that you were a bit haphazard and not reflecting upon how telling what you'd done to your friends would of course make rumors, and that she might not enjoy that. That's done, though, so give her the space she's asked for. But you really should also ask for more space for yourself. It's going to be strange enough seeing each other at work, and if you are going to do social things on the side of that, I fear that one party - likely you - will end up having growing feelings, and will be hurt. I'd definitely recommend politely declining hanging out with her on the grounds that you have feelings for her. Then you're honest about how you feel, while you take care of yourself and don't just go where she wants to. The 'being together in the future' is also irrelevant, and you need to put it behind you, so you are open to meeting new girls, instead of waiting for what-could-have-been
what can be changed is their enjoyment of that time spent interacting. I'm an introvert but enjoy spending time with others. I just need some alone time at some point in the day to gather my thoughts.
