my friends boyfriend

I met this fantastic guy and over some time we grew closer and then we had sex I lost it to him and it was great the sex was hot and rough then this one time he asked me if he should get at this girl and I didn't think anything of it then it turns out he was dating my friend and whenever she talks to me about their sex life I want to tell her I had sex with him but he told me not too and whenever I see them together I can only think about having sex with again. I'm with a guy now and when we have sex all I can think about is my friends boyfriend the guy I lost it too all I do is compare them and think how much better sex would be with the other guy and not with the one I'm currently with