Confession

My best friend is a guy and we grew up together. We've always hung out a lot and recently I started to have feelings for him, the only problem is that he has a girlfriend. Well the other day we were hanging out and we ended up kissing, and now I don't know what to do. I've been trying to avoid him as much as possible because I don't want to be around him and have the same thing happen, until he breaks it off with his girlfriend, if he even plans on leaving her for me.