Dude, I've been here, and here's the thing: nothing will ever go anywhere with anyone if you don't say anything. Sure, there's some ways to go about flirting, but if she's eyeing you and you don't say anything or try to ignore her because you're nervous, that's just making it look like you're not interested either. You've just got to go up and do it. The worst thing that could happen is that she says no, but at least then you know her feelings, right? And you aren't going to know if that other guy is her boyfriend unless you ask. You don't have to be super cool or over the top. Just catching her eye, nodding, and then walking over and paying her a compliment and then asking for her number is fine. And if you do get talking, do some research into "push-pull" so you can really impress her. Otherwise, you're just going to keep on doing what it sounds like you've been doing for years. Thinking about what could have been, and all that is doing is adding to your anxiety and depression. I know it sucks man, and I know we all wish that there was some magic way of getting the girl to kiss you first like in all the movies, but unless you just did something that's heroic or cool, it's not going to happen. And even then, she'd most likely be to shocked to say something. Just take the plunge. You can't soar with a hang glider if you don't first take the plunge.

You've got this (: