Most Helpful Girl
I can say this from the perspective of myself: a kid who's parents stayed together only for the kids.
I felt awful knowing my parents didn't want to be with one another. There was constant arguments and fights and life itself was unpleasant to the extreme.
Your unhappiness will affect your kids. You will only teach them to stay in a situation what is unhealthy.
Do not do this. You hurt yourself and everyone else around you when you make your own life miserable.
Most Helpful Guy
I would have taken the woman from work.
I don't like the sound of your wife coming around again. It sounds like she and the other guy split, so she needed a familiar fallback (you). It sounds like if the divorce went through and she had to try to sustain herself she probably wouldn't have been able to do it on her own.
It doesn't sound like she is putting 100% into you or the marriage, and it takes two to tango. She was already cheating on you, and was fully prepared to call it quits.