I've been nc with mine for many years.
I found it very difficult when my kids hit the age I was when various things happened and then a whole mess of stuff came out and I cut her off.
It hasn't always been easy, my siblings had very different parent to the one I had so I no longer talk to them either now.
She got endless police welfare checks done and said I was suicidal etc until she got a warning, and then reported me to SS monthly for abusing my kids.
These were the only ways she could think to further abuse me.
It all settled down when my brother and his partner split and her venom was then directed at her instead.
I had age appropriate chats with my kids about what I was subject to as a child, but, if my kods wanted to I would have still facilitated a relationship somehow between them and her, but they didn't want to.
Apart from a rough couple of years when she was still trying to control and manipulate me it's been a relief.
I've got myself to a point where I simply feel nothing about her now, no love, no hate, just nothing.
Only you know if you can still maintain contact, but just do what's best for yourself and your kids.