I love your proposed conversation between FB and her H. I had a similar conversation with my H when we first got back together. Even today, I will ask him if he talked to the OW and he will say just business and that's it. Unfortuately, they work together but not in the same building. They work in the medical field. He said she will try and start a conversation via IM and he remains business with her and ignores everything else. At least this is what he has told me. And I believe him until he his behavior tells me something else. In the past I could always tell if he was talking too much to another female because he would come home and ignore me. Like he was feeling guilty about it. But I have not experience at all.
It really doesn't matter if it's "all business" or not (and he's already admitting, that from her side, it's not) -- CONTACT IS CONTACT. Physiologically, each new contact with a former affair partner gets the endorphines (PEAs) running in the brain again, and basically re-sets the withdrawal clock to 0:00:00. In fact, even NEGATIVE contact (say, a fight or a disagreement, or a co-worker passing along a negative rumor about the woman) will set your husband back.
There is a saying around here and other marriage forums, and that is "No contact is no contact -- PERIOD." That's about right.
