I have been reading your sitch but haven't commented lately because I find it a bit painful to read.
Being a non-custodial mother who previously was ill with depression, I have the ability to see your sitch from both sides and in a lot of ways, I feel for your XW.
HOWEVER, I wholeheartedly agree with what you are doing to protect your kids and I think you are making good progress and that you and the kids will do well in life.
I just hope that your XW tries to help herself after you are gone and does something with her life, as it's such a waste.
Well done, though, for helping YOU and being there for your kids. And you did TRY to be there for XW too so I think your actions have been very commendable.