Sorry you had to learn about the affair. I'm even more sorry that their actually was one. Of course, she doesn't see it that way.
It doesn't matter if your wife heard the vows. She'd see it entirely different from you...she'd probably be like, "don't do it."
My question: Why are you paying spouse support and for how long will you be doing that? Can't she get a job? I didn't read your whole story, I'm sorry, so if this was ordered by the court I understand. I just hope it isn't out of some obligation you feel towards her.
You cannot be lonely if you like the person you're alone with. Dr. Wayne Dyer