I think you posts resonate with me because we are, in some ways, making the same life mistake. We are defining ourselves based on one mistake or one characteristic. And we refuse to forgive outrselves. We view the flaw as permanent and unchangeable. Which robs us of any motivation to change and grow.
You are not defined by your affair. Neither is your relationship with your H. if you insist on defining yourself as the villain and your H as the victim - despite all the poor treatment that you have endured from him - then you consign both of you to purgatory. I know how tempting that is for those of us with martyr / masochistic tendencies. I am doing exactly the same thing.
But it is the wrong choice. For both of us. I don't expect you to choose differently based on my posting this. I do not expect to ever choose differently, either. But it needs to be said forcefully that what we believe about ourselves and what we believe about our spouses is false. We are living our lives based on known falsehoods.
I bet "smart" is an adjective many people who know us would use to describe us. if they only knew the truth.