In my case, it was a “three strikes” thing. See, my ex had slept with an old girlfriend the night before we were married - something that caused drama in the first year of our marriage but that I forgave him for and we moved past. Then he had an affair 17 years into our marriage - I found DB, worked hard on our marriage and myself, and we reconciled. We actually had several good years. Then 7 years later he had two concussions, asked for a divorce, and left after a few months. By that time I felt I had done everything possible to save my marriage, and that after three times, there would be NOTHING he could say or do that would ever cause me to trust him again. The day he filed the divorce papers I was done.
I actually wish now that I’d divorced him when he’d had the previous affair. I’d thought I was reconciling for the kids sake as well as for myself, but my kids told me much later that they were always waiting for the other shoe to drop. I think it was just as much stress for them as if we had split then. ( And my ex had never moved out of the house, and his affair only lasted 2-3 months).
My mantra at the time was “let go or be dragged”.
And I’ve come to recognize since my divorce that my ex is a narcissist. My life is so much better not having to walk on eggshells around him, trying to keep him happy. I wish I had not wasted so many years on him.