One of my former co-workers was aware of the affair, and she saw the things that my wxh did to try to make things right with me.
One day, she said "when are you going to forgive him?".
Well, at that time, we happened to be on a bus tour. I spent 4 hours giving her the history of everything that happened during his affairs.
After that 4 hours, she said "I hate him for you - NOW, I understand".
So, I think the only people that really know what happened in a marriage are the 2 people in the marriage - sometimes, both of them don't even know what's going on.
Trust yourself, people. Trust your gut.