If this is really not an option, you might want to try to avoid him for awhile. If you are just starting to have romantic feelings towards him, try to rationalize it and move on by focusing on the friendship. If the feelings are much greater and have developed into a serious infatuation, then you should stop seeing him for awhile. Trust me, it's an unhealthy situation that will most likely become more problematic down the line. Best of luck in trying to get over him.
Lovers come and go.
Good friends are very hard to come by. I've gone through many boyfriends, but have kept a close circle of friends. Be thankful for what you have.