I believe feelings are neither right nor wrong. Only actions can turn out good or ill, be right for us or not. That you married when you do not believe you should have and still believe that, I don't think you can "fix" by staying married. I don't know how the person you had an affair with feels about you/now but I would work to get to a place where I was enjoying my life and being who I feel I should be, as honest with myself as I could be. If it took divorcing my husband I'd have to do that or feel a liar and like I was working upstream with no purpose.