Back in high school I fell in love with my friend's girlfriend and that came between our friendship and now we don't talk anymore
He knew about your feelings?
Yes, he noticed that I'm in love with his girlfriend and we got into an argument and we don't talk anymore.
You shouldn't feel that way for his girl. Let them be them and you guys can be friends.
I can't be a friend to someone who cares more about his girlfriend than he does about me.
It seems like your relationship has been badly damaged, do you believe you can still salvage it? While it was wrong to go after his girl and mess your friendship, you can't change the past and you still have time to make it right! How about trying to call him up to see if he'd cooperate?