not getting far

I have cheated on my boyfriend twice. I feel guilty because I "got away with it", but now I realize I didn't get very far because I still have to live with the guilt of knowing I did it. I wish I could tell him, but I know that is not what is best for eiter of us. If you cheat on a partner there is a reason why and if you are deperate enough to cheat then the relationship is over , maybe not actually, but phyiscally, and emotionally.