I have to say that I agree with some of the others that there may be OW involved. My husband had always said and I believed he would be the last person on the Earth to ever cheat, but I was wrong. Although it is painful it is better to know the truth.
I hope it gets easier for you and you are correct in thinking it is a waste of time trying to figure H out. I have tried and still try to figure out my H and it just isn't working. It is actually making things worse for me and pushing him away. I'm sure you are seeing the same results.
Keep "talking" to people on here. I read on here constantly and am starting to post more and it does help. I can tell you that the pain does get a little easier. The first month and a half of my separation, I don't know how I functioned. I am not sure how I taught my classes and in between I would just hide and cry. It is easier now, although still painful, but I don't sit and cry all day every day anymore, so that is good.