Do WHATEVER you need to do. You come first. Nobody else is gonna look out for you.
I divorced my BPD wife a few years ago, fully bluepill but I had somehow found enough sense to realise that she was crazy and fucking me up. We had 2 young children. Being a bluepill schlub I played by the rules, tried to keep things amicable, and basically gave in to whatever she wanted in order to keep contact with the kids. Eventually things ramped up, of course, and she took more and more blatant liberties and open abuse of my "good nature", all but throwing them in my face, until one day she pushed too far and I snapped. My girlfriend at the time said I came home and sat in the corner of the bedroom without speaking for two hours. Total zombie. I vaguely recall I was pondering how I could kilo myself with items we already had in the house right then. My gf took me to the doctor who said I'd had a mental breakdown (at fucking 25 years old) and kept me off work for a month.
In this downtime period I retreated into quiet hobbies, somehow clawed myself back together and emerged as the beginnings of a red pill man. I realised that while I still had contact with the kids, she always had access to me and a vulnerability to exploit. I looked into going for full custody. Every lawyer I spoke to said not to waste my money. So I decided to cut ties and save myself. I saw them one more time, I had a fun weekend with them, I cried a lot and hugged them and then took them back and they were gone. I told my ex wife via email that that was the end, explained that it was due to her behaviour (probably pointless but this was pre redpill) & then blocked all possible forms of communication from her. I mourned my kids for a while and then I gathered my shit up and moved on with a clear conscience. And I'm alive, and free.
If they want to seek me out when they're older, old enough to interact without her involvement, I would love a relationship with them. I'll explain my side. If they don't want to know me and feel I abandoned them, I'll completely understand.
I got out. I had to scorch the fucking earth but it was that or death and I wasn't ready to die. It was the hardest but also the best thing I ever did. I feel bad for those kids, but I couldn't save them and I would only have drowned in the shit myself by trying. She's a capable enough mother, they'll survive, even if they're psychological wrecks as a result... That was a given either way. Maybe I can help untangle the mess when they're older. Maybe not. But I had to put myself first because nobody else would and they'd happily let me die otherwise.