You have a whole community of people here who care about YOU.
You haven't messed anything up. Be kind to yourself. You don't deserve this and it is NOT OK what he did to you.
An a few questions:
Is there anyone IRL that you can talk to? A friend or family member who you trust? Do you have an IC?
Is there somewhere you can go for a few days to get a bit of space? If it is too hard to think of it like leaving him, maybe framing it to yourself like you just need some space and/or a break can allow you to get out of the house?
Are your worried about your children at all?
Would it help to think of your H like he is on drugs and not the same person as the one you married?
I really, really think you need to get all firearms out of your house ASAP. Violent, erratic behavior and guns do not mix.
Please do keep posting and let us know that you are safe.
Me (46) H (42) M:14 T:18, D9 & D11 4/19 - 12/19: series of escalating BDs 9/20 - present: R and piecing