Threatening to stonewall you is another way of abusing you.
This isn’t a stable home for your children. Once they are settled elsewhere (or he is) and they come to terms with the change, they will adjust to a new family situation.
Don’t be scared by stats about lone parents and childhood outcomes etc. It is always better for a child to live without the spectre of domestic abuse hanging over them than to remain with both parents together where one is abusing the other with shouting, slamming, the silent treatment etc.
I honestly know what a hard choice this is to make. I had to end my 9 year relationship last year for similar reasons - he would (very occasionally) swear at me and throw things, but not at me, just in general.
He was so nice the rest of the time that each time it happened I would try to work out how to prevent it happening again and keep the loving vibes we had 90% of the time. It was a tense atmosphere sometimes and I tried my hardest not to rock the boat, but got to a point where if he asked what was wrong I’d say “nothing, I’m fine” because I knew it would escalate. Then he’d push it, saying he could tell I wasn’t fine. I’d tell him I wasn’t going into it because I knew how it would end. He’d push it again, I’d finally try talking in the gentlest terms possible and bam! Massive argument ensued where he would be nasty and end up slamming doors and leaving.
It was like Groundhog Day, I could tell you word for word how it would go, and nothing I did or said would change the outcome.
If it was just the one slammed door in anger I’d say a conversation about acceptable behaviour and boundaries was worth a try. But it sounds like an ongoing pattern of intimidation and emotional
abuse. The only influence you can have here is on your own reaction to it. You can’t change him. You can only decide what sort of life you want to live.
Its taken me over a year to get over my breakup and I still have the odd wobble where I miss him. But I know I 100% did the right thing for myself and my kids. They have seen that I’m not willing to accept such shitty treatment and hopefully they will all grow up with better relationship expectations because of it. You can do it. It will be hard. But it’s necessary for their well-being as well as yours.