<<  I used to mean the world to her.... now she's found someone so much better after we kinda broke up.  >>
I dated a girl for a year or so, we were extremely close... she started dating a guy a week and a half after we broke up... she became engaged to him within a month or so.  I was really tempted to be hurt, but then I realized something, and it's something you should realize, too...
She's the problem, not you.  My gf had major issues, that eventually made this new guy break up with her.  Bets are, this new guy'll do the same thing for her.