Ashamed

I'be been seeing an old associate of mine. We really didn't talk much back in high school but we're mutually friends with everybody of the same group. Here it is 3 almost 4 years later and we've kinda fallen for eachother. Only problem is I have a boyfriend and he has a girlfriend. We haven't done anything sexually, not even kiss. We leave it to a minimum hug everytime we hang out. But we talk about it often about how we both want to. I love my bf but I really like this guy and I can feel myself getting drawn to him. But I can't see myself being with him forever. I really just wanna have sex with him anytime I want to. I know that's not right but I can't hide my feelings for too long. What would you do? I just needed to rant.