The main points you want to touch on in your response are:
-Valdiate W's POV that things aren't great now -A D isn't what you want, but you will not stand in her way -State that you are not willing to live in an open M -State that you are willing to work on the M given that the OM is out of the picture -State matter of factly that there is ample data that supports evidence that it's best to have an intact famlily
Yes, all of that ^^ can be accomplished in 2 to 3 paragrahps that comes from a place of strength.