Since he is willing to go to MC, I would go. Just make sure you find a good MC who is pro-marriage. Our MC was trained by Michelle and will do everything she can to preserve our M, which not all counselors will do.
It sounds like he has work to do on himself.
Were you both each other's first? I honestly don't know if that would make a difference if you weren't... H and I married when we were 45 and 37, he had been married several times before and I had a teenage son from a previous relationship - so obviously not each other's first. It still felt extremely intrusive, violating and all the other feelings that come with broken trust. I think that when you enter into an exclusive relationship like M, it's like you start over and anything you did before, doesn't matter.
M 16 yrs, WH62, P54 3 adult blended kids EA 11/13, BD1 6/14 PA fall 14, BD2 2/15 Piecing 2015, BD3 12/15 Separated 4/16 WH moved OW in 5/16 Divorced 6/15/17
It still felt extremely intrusive, violating and all the other feelings that come with broken trust. I think that when you enter into an exclusive relationship like M, it's like you start over and anything you did before, doesn't matter.