mb28, While I have no personal experience with infidelity in a marriage, I can say that I have been almost obsessively reading this message board and I have followed many sitch's for a very long time. It seem that strong, quick decisive action seems to work best. "Shock and Awe" kind of thing. Knock the cheating spouse on their butt with your confidence to not cave on any of their demands and absolute refusal to get sucked into conversation etc. unless the affair ends. TO own their own mess and hit bottom, to let some friends and family know so that the end of the marraige is not conveniently "mutual" but one-sided and people know it. I read many that try to outshine the other person or not rock the boat too much or read too much into what the cheating spouse states. It seems like being Plan B is somewhat acceptable. Or don't set boundaries quick enough or let the cheating spouse continually "rule the show".
You may want to read RockedWorld post in piecing and previously in Newcomers to see how she stood her ground as her husband wanted a D to continue his affair with his 24 yr old OW.
M38, H37 S3, S7 Together 15 yrs Married 8 yrs Bomb July 2008 Inhouse separation "I hate you" "We are over" (too many times to count) Reconciled Sept 2009 (still worth it)