1. Holy fuck to that dude who had a girl ask him to marry her after 2 weeks. I know you said in your post that you were going to end it, but you didn't say it with enough confidence and certainty for my liking. IT DOESN'T MATTER IF YOU GUYS HAVE THINGS IN COMMON (ooh equally diverse world views); FUCKING END IT. She is either trying to scam you, has ridiculously perverse family values, or is FUCKING CRAZY. RUN.
2. There's nothing wrong with a 24-year-old dating a 19-year-old. That guy who said you should never do it is wrong. It's true that a lot of 19-year-olds will be immature and annoying to have to deal with, but conversely there are some really cool ones out there too. Using one fucking instance of when it didn't work out for you personally (addressing this to the guy giving advice) to ward off all men on doing it ever is ridiculous. If you're interested in a girl and she's that age, then use your judgement as to whether you think she would be a good person to get involved with. That's all that matters. Don't worry about age when it comes to being 19.
3. Create a damn Facebook profile. If you don't want people to find you, call yourself "M Works". If you don't want your last name up there, call yourself "Mike W". Add your friends to it, get some pictures up, put up some seemingly meaningless info (favorite books, etc), and you're done. I suppose if you are very identity-conscious this could be an issue for you, but if it isn't, then just do it. I've personally never given out my facebook name/info for any dates, as I see it as potential for regressing into friend-status. When I meet a girl, I go straight for the phone number then straight for a date. No need to pussyfoot around. I suppose if she asks you for your facebook info, and you're comfortable with giving it to her, then ask her out during that very conversation. "Yeah, my name's Mike Works on Facebook. There are a bunch of Mike Works, so just look for the one with a picture of me in front of the Eiffel Tower. By the way girl, you so fine, let's fucking smang it or some shit this Friday, fuck shorty" (it's early and I'm tired right now). Killer instinct, boys. Confidence. If you view her connecting with you via Facebook as a roadblock, then let her put it up, and then immediately knock it down. Go for the jugular. Be a man.
Man, I really don't want to go to class right now, I just want to listen to rock.
THE JUGULAR, BOYS