OP, I'm in my 40's now, but when I was a kid, my Mother's boyfriend would have walked over broken glass for me. He was, in fact, more caring than my own Mum (another story altogether). When I was a teenager, it was he who drove me to the swimming pool five days a week at 5.30 in the morning for training. When my partner left me in my mid 20's, it was he who hired a van to bring me and my stuff home and wanted to rip the arms off the boyfriend for hurting me. And countless stuff in between that made me feel safe and loved.
The point I'm making OP, is that your children, should never, ever be regarded as worthless. If they are treated as worthless, then I think I would do that person harm (if it were me in that position). It's a line that adults shouldn't cross. Ever.
It sounds to me (and I say this with the best intentions OP, I don't want to hurt you), that you are going back to the same personality type in a partner. If you can't stop that cycle for yourself, then for your DC's sake, you must do it for them. You are in a position to kill this relationship, once and for all - you don't live together - you and your children must be safe.
I'm sorry, but whatever nice words and gestures are said in between the bursts of anger, bringing your children into it would kill it for me. He'd be gone.
And, FWIW, he wants you sorry and contrite, and grateful for him for 'saving' you from your previous narc relationship. He wants you grovelling and weak and controllable. The fact that you are not makes him show his true colours. Make the final cut to this disturbing relationship OP.
Good luck.