I caught my husband w/ Rosie Palm. HELP!!!?

My husband knows that I don't care for him doing that behind my back, but yet did it anyways.I'm really hurt about the whole incident, because if he does that kind of thing i feel he doesn't need me anymore or is not interested in me. He says that he loves my body and that I'm pretty but why would he do this to me. I'm sorry but this hurt my feelings, and now I'm afraid to trust. Should I let it go?