My boyfriend admitted to having a one time sexual encounter. We have since decided to work on a relationship. His excuse was that he was out for a few after work drinks and one thing led to another with a so called "friend." OK, before our sex life was active. However, now I really no longer find him sexual attractive. It's like all that passion has went down the drain. I have not told him this. Is this a common problem to deal with after infidelity?