Cathy, I totally feel for you and understand HOW you must feel. My H is not home, but told me he told OW to move out... but I still feel certain there is a lot of contact. I am very uncomfortable about the whole thing. I think my H is trying to keep tabs on us, but do his own thing with whoever he is doing it with. He is not forthcoming at all with what he is doing, yet asks where were you, what time did you come home, who where you with, etc. I find the whole thing very hurtful.
Anyway, all I can say is PATIENCE. Clearly, if you start asking questions, you may drive him out again. Something brought him home. That is a positive. I would say (and, as you know, I am not in your situation) no R talks. I think as women, and as the LBS we want to fix things, to ensure that it won't happen again, to talk, etc. But we can't go there. We can't even get in the same neighborhood. The A has to burn itself out. You can be loving, funny, etc. Be you. But live your life.
Take care of yourself. This is just another step, unfortunately, we are running a marathon.
Relax. Appreciate. Be calm. Laugh. Enjoy. Be secure. Be loving. Be loved. Don't personalize. Don't ASSume. Accept. Be grateful.