My opinion is that it's her business, and up to her what she wants to do. You and your wife are divorced, and as painful as it is to learn all of this, it no longer concerns you.
Divorced or not I guess it is naturally of concern because this was his W - divorce is just a piece of paper compared with so many years of marriage and family life and the kids are living in this garbage. So perhaps "not in your control" is really what to keep in mind as the Serenity Prayer says http://en.wikipedia.org/wiki/Serenity_prayer
