This girl is ruining my life....what should i do?

hey so I'm a freshman in college and in a fraternity. Anyways I met this girl who is in a sorority and lives in my building and i have been madly in love with her ever since the first day i saw her six months ago. Needless to say she is all I think about. She keeps me awake at night and is the first thing I think about when I wake up. I go sick parties/mixers every weekend because I'm in the best frat on my campus, but I don't even talk to other girls cuz she is the only girl I like. I hooked up with her a few times but that's it. Anyways I was supposed to take her to our formal (a weekend in wildwood NJ where we share a hotel room with our date). So i was really excited to like make a move on her finally after months of waiting for a chance. A week before the formal she told me she is back together with her boyfriend who goes to another school and can't go. I have been a wreck ever since. I don't know what to do I'm really depressed about it and don't know what to do. The formal is friday and I don't think im gunna go. What should i do......