I think the one you stated a few posts above was a good one, H2BM.
What are your very short list of "Boundaries of Personal Integrity?" What are the things that go to your core -- who you are -- that, if violated, make you feel horrible and not true to yourself?
In my situation, when my wife was having her affair, my boundaries were:
- no calling (or receiving calls) from OM while inside our marital home;
- no texting OM in front of our boys, regardless of where you are;
- NO LYING TO OUR KIDS, or to your parents -- if you do, I will tell them the truth;
- no leaving the boys home alone unattended -- or without a meal -- for any extended period of time. If you're going to run around and cheat, I can't stop you, but we neec to communicate to make sure our sons' needs were being taken care of;
- no coming home very late (I don't think I ever put an exact time on this, but one night she came home from being with OM at about 2:30am, and I had all the lights out and the house locked up tight and came THIS CLOSE to putting the security system alarm on. I told her "I won't have my own home treated as a hotel while you carry on an affair; if you're going to come home that late, do us both a favor and just stay out all night and don't come home at all." She never did it again).