Hi there. Sorry I have never seen your posts before. I did well to hang on for so long.
It sounds like your H is wanting to be taken care of and have no responsibilities. He seems to have that with his OW, mother, and you. Maybe it's time for him to know that you aren't going to be there in any way other then a friend to get him to see what he is missing. It sounds like you have your head on straight and have a great attitude. Regardless what happens with your M, you are going to be ok.