My grandparents and W's know about our S now. Her grandfather emailed me this morning offering his condolences and saying I'm welcome in their home anytime regardless of the outcome.
My grandfather called me and shared some sound advice, and recommended a book, Love Must Be Tough, which seems to be in line with DB principles. He inquired about the "why" and I acknowledged it involved someone else.
Tough stuff, UC. When my wife complained (SEETHED is more like it) about her telling her parents about her affair, I simply told her "I love and respect your parents too much to lie to them. I would NEVER lie to them."
Meanwhile, she was lying to them.
When we reconciled, there were two main things my wife said were a strong pull on her decision to come back to the marriage. One was that she missed me as her best friend; and two was the disapproval of our adult daughters and her parents was killing her.
FWIW. Exposure isn't advocated by MWD, but I would certainly never advocate anyone LIE, either, if asked by a beloved family member.