Quote: What if she had cancer instead of a mental illness what would you do then ?
Very wise consideration. Yet, just as you wouldn't be able to control her approach toward her cancer, nor its outcome, you need to let go of any desire to make a specific outcome occur. This is her work. Her issue.
Just as loving parents love themselves first, I think great DBers take awesome care of themselves, pushing for as much personal growth as they can. That positivity will eventually affect the WAS, in ways unknown, but therein is your work.
I admire your steadfast fathering of your teens in this situation. That's the sign of a true man, and you'll have your pick of available women if it comes to that. But take great care of yourself - first.
Merry Christmas and Happy New Year to you and yours! I hope you experience great peace and happiness in the new year.