It seems to me that maybe he should speak with a counselor, if he is able to? I don't know that you should play the role of confidant about his affair to that extent. Someone else who is not involved at all can also point out to him how hurt you were and such.
As far as the whole lubrication thing - I've never heard of "too much". I think it's just an excuse for him not being able to emotionally at that time. He certainly doesn't want you dry! Dryness really can be a problem.
