That sounds SO toxic for the kids. How sad.
Your text sounds on point. However, I hope you are not downplaying the affects this has on you or the children. We Codies are always moving the line in the sand back further and further. If her children don't want her to attend events, and one child has moved out, then she is not a good mom. Period.
If she is playing the blame game, she is not in recovery, period.
I hope you take good care of you and the kids!