I did the exact opposite with my wife. I told her that if she chose to end our marriage this way -- by having an affair, lying to everyone about it, and cutting-and-running from the marriage, with no MCing -- then we would not only not be BEST friends, but I could not even be her friend. Because friends don't treat each other that way.
I told her I'd always be civil to her, and we would of course communicate in order to co-parent our children, but I could never be her best friend again.
This really shook her up, and -- along with my exposure to our adult daughters and her parents -- were probably the three things that did the most to bring her back to the marriage.
