You've done some work, and I like and understand your last sentence above.
Your current R with your W isn't such that you'll be able to talk to her about her illness. This is her path to walk. You've said your piece, now leave it.
I must have missed in your earlier posts the issues with alcohol. That's a real game changer and adds yet another layer of complexity.
These ^^^ are all her issues. You have to focus on you. Google Depression Fallout, it might be of some help.
Me 57/H 58 M36 S 2.5yrs R 12/13
Let me give up the need to know why things happen as they do. I will never know and constant wondering is constant suffering. Caroline Myss