My own guess at what Jesus would do? He, of course, as you mentioned, would forgive. He would also probably do what he could do to most ensure this person’s salvation.
By far, most of the responses on this thread are not oriented that way. They seem to be selfishly motivated. Is this man’s salvation best served by being deserted by his wife? I don’t know, but the fact that this question is not being asked is what bothers me. What appears to be happening are most people are making decisions on what they want for themselves, to satisfy their quest for emotional retribution.
Maybe leaving him (temporarily) would most ensure this man’s salvation, but I don’t think so.
Sincerely,
Dan