Sheila, don't give up on your M. Your H sounds like he's trying really hard. Its human to make a mistake even a bad one that hurts someone you love. Don't throw your M away because its not perfect.
Don't believe that all you are entitled to is unhappiness. Get some insight into why you are destroying the thing you want. I think that like me you are pushing for the one thing you don't want.
I know I have been sabotaging my own rebuilding efforts. If my H left or the M ended it would destroy something in me and break my heart. Its the last thing I really want. So I am trying to look at why I seem to be hell bent on letting it go. WHo would I really be punishing?