Hi Kappy,
First let me say that has to be the worst emotional torture to deal with when they are still home and having an affair and treating you like c**p. My hat goes off to those of you who deal with this. I know I couldn't. I would not be strong enough and am the sort of person that can't hide my feelings. I'm not a good actor.
I do have a close girlfriend however that has been living with this sort of c**p on and off for a few yrs now. Lots of our friends think she pathetic for putting up with it, but I think she is one of the strongest people I know. She has a very healthy self-esteem and never lets the comments get to her. She's knows they're not true and she rises above them. She goes on with her life-even takes the kids and goes off on vacation. She keeps up with her tennis, acting, work, and friends and includes him when he intitates it. She never demeans him, and treats him with respect. She pretends she doesn't know about his OW and in her eyes she treats him as she always has-with love and respect.
I think he respects her more than ever for it. He knows he's a $hit, and in his eyes she's the best thing that ever happened to him-he knows that down deep but often treats her poorly. She just doesn't take it personally.
Not all people hear would advocate this, but she doesn't even know about this forum etc. she just has choosen to deal with the situation in this manner.
He seems to be coming around and has made progress, but he does keep running back so I think the others on this forum would be better able to help you deal with giving him some boundaries etc.
I'm not sure how much that helps, but there are many on here who will come to your aid.
Take care