Stop asking her to defend her negative thoughts and actions. Next time she goes off on you just tell her, "it must really be hard being you, I am sorry if I am contributing to your misery in any way." Agree with her and walk away. If you truly seek understanding then let it unfold. It's not your place to rescue her from her decisions. Agree with her and watch the drama go away. Nothing to argue about when you are both on the same side. She brings up D talk just defer to your L. Just agree that she must be hurting. Watch the dynamic change.
Compassion, empathy, love (philia) and strong boundaries.
"What is best for my kids is best for me"
Persevere = happily being patient over a long period of time