There were three things in my own sitch that probably provided 90% of the "jolt" to my wife's affair fantasy (OK, so me filing for DIVORCE probably ultimately did that, but I'm talking before that):
1. Losing my friendship. She told me when we reconciled that it was this more than anything that she missed. I had told her very plainly when she was in the throes of her affair, that "Make no mistake -- if you end our marriage this way, by having an affair and running away from it, without trying to work at our problems, then I will NOT be your friend. We will be civil, and co-parent effectively, but I will never be your friend if you continue on this path. If, however, you end your affair and come back to the marriage, and we try to make it work and it doesn't work say after 12 months of trying, including good MCing . . . then yes, I could see where we would remain friends, even in divorce.
2. The disapproval of our family, especially her mom and our then-18 year old daughter.
3. The financial reality that I set up and allowed her to feel.
If she wanted out, she had to put on her BGPs and get out. I couldn't stop her from fleeing, but I damned sure didn't have to finance the flight.