You know, if you're at college you will probably find a counseling center on campus that can help you with your fear of abandonment. I say this because you could have some serious problems later on with your friends if you don't address this issue now. Your old friend was a dick, who proably had problems of his own- it's hard to let go when someone hurts you and betrays you like that. Go talk to someone about this, they'll help a lot, and then you can begin to see things in a more positive light.
DON'T EVER DATE YOUR BEST FRIEND'S EX!! Course, I'm a girl, and things are a bit different in girl land. But anyway, that's my advice...
Plus, dude, you're in college... you're gonna change a lot in the coming years as Cim said, so who knows who you're gonna end up with? Just have fun!
__________________
Sage knows our mythic history, King Arthur's and Sir Caradoc's
She answers hard acrostics, has a pretty taste for paradox
She quotes in elegiacs all the crimes of Heliogabalus
In conics she can floor peculiarities parabolous
-C'hi