Quitting a tenured position is a very big deal. Did she want this move or was in your idea?
Who knows about this affair? Have you exposed it to anyone?
You need to be very firm about the affair, but you also have to offer her a soft place to land if you expect her to come home. This will take time. A lot probably.
I'm a man . . . But I can change . . . If I have to . . . I guess . . .