Sorry this is happening with your D. It is a tough thing to deal with as a parent.
Have you thought about family counseling with D to work through family issues? A neutral third party person may be able to lead XW to see the "light" that D is acting out because there's no firm set of boundaries nor parental guidance.
This way, XW cannot target you if you broached the subject with her. The neutral third-party person can facilitate it for you and the family.
