OK

First and most important question :

What is the status of the other person?

Is she continuing to persue him or was this a one time thing and she won't be doing it again?

You completely left out the status of the affair itself.. is it ongoing or has she taken the steps to end it?

Did she show remorse or did she just casually tell you "its over" and is going right back in to work?

You can repair a marriage after infideilty, but NOT if its ogoing.. ALL CONTACT with the affair partner MUST END completely

What is the state of their contact NOW?

Is THAt over yet or is she working with him every day still?