Its all about feeling safe. and when you have been betrayed, that safety net is gone. We tend to disguise it with anger, being hyper vigilant, playing the mind movies over and over again. That way we will not be fooled again. I know, its exhausting.
I am trying to live in the moment and trust my FWH, who continues to do everything right.
I, also, now know how he acted during the affair, and if I ever saw that type of behavior again, I would know. During his affair, I was naive and unexperienced about infidelity. I now consider myself an expert, and that helps to make me feel safe.
Hugs to all that suffer, it will get better.