I'm still infatuated with a girl I only met in person a couple of times over a year ago...

You kinda gave just your side, and didn't say anything about how she felt, just that she had a boyfriend. If you are really serious that you love her I wouldn't give up on her that easy. If you are done with high school, maybe you can move closer to be with her while in college, whatever... Life has a funny way of rewarding you when you do things for yourself, like one time I kinda felt the same way about a guy and he was hooked up with another girl, and I kinda didn't give up talking to him and stuff and then met his friend and was really in love with his friend. Sounds weird but it's the truth and truth is stranger than fiction lots of times.