For the record, I exposed to:

- OM's parents
- my MIL and FIL and my BIL
- OM and W's employer (affair was happening, in part, at their place of employement)
- my parents and siblings
- our adult daughters (then 20, 18). I later told my S14 in an age-appropriate way, when he asked me why me and his mom were fighting so much ("Mommy has a boyfriend, (S14). Married people shouldn't have boyfriends and girlfriends -- it's not right. I've asked your mom to stop, and she won't, and that makes me very angry, and that's what we're fighting about. I thought you should know the truth, and I will ALWAYS tell you the truth, okay?")