I pretty much concur with J9. There is a point where you are just sick of the pain and wasted energy on something that really isn't going to make things any better anyways.
it's been 10 years for me. I have learned to live without apology, remorse, him marrying OW and her being my daughter's stepmother. I just got tired one day of being angry, of wanting to know how he could possibly do this to me when pregnant with our daughter via IVF. I was 27 years old.
I turned the focus on me and my daughter. I became the best me I could be and the best mother I could be. And I think I am pretty amazing at it all. I have since furthered my education and my career, I have always done well for myself and my daughter. I simply take pride in that.