North, I would be furious if my H was sneaking OW into my house!! I questioned him about that at great length. I know she was here from time to time, but he swears he never slept with her here. He thought I was nuts for even thinking it.
I would definitely state in no uncertain terms that she is not to be in your house. Set some boundaries. I don't know how you enforce that other than giving him an ultimatum of some sort.
I don't know if I would contact her H. This subject has been brought up before on this board. Do you really think it would do any good? Think about what would happen if you did (I'm sure you are). Would it help your sitch? In my case, it would not so I have not really thought about doing that.
The best thing I have done to show my H that OW was not for him was to use DBing techniques. I have been consistent in my efforts to show my H that I love him, but yet have not pursued, have controlled my anger, etc.
What has helped me is that he never left home. Because of that, and the fact that I wanted to work on our R, OW has become desperate. She is the one who is pursuing, getting angry, etc and that is burning off his fog!
If he is still at home, then I say he is still very foggy. The best thing you can do is DB. But I think it's equally important to show him that you still care. Do you get to spend any time together?
