Do I tell him now or should I keep it to myself?

My husband is loving and wonderful and works very hard for us. We met in college and hit it off though he was very different from other guys I dated. He is very responsible and mature and he dresses like men much older, ll bean and stuff like that. I love him so much. But when we were dating I used to also go out occasionally with other guys. He knew about it because they were usually friends of the family that my mother asked me to take out. It was usually platonic but on one occasion my mom's college friend's son was in town and we went out and I ended up doing something stupid with him. We did not have but I did everything short of that for him. I feel like its been several years and I am holding this in and I want to be honest now. Should I let him know that I really messed up? Or do I keep it to myself? My friends are divided in what they say.