There is a lot to unpick here OP.
It' s really not as simple as he's being a dick so he has to leave.
This is going to be long so bear with me.
I'm not going to give you a 2-line post like 'Kick the bastard out'.
I'm pretty much your age so have the handle on older men, my parent's marriage, friends' marriages etc. I think older men can become grumpy for a whole range of reasons, which they can't unpick themselves.
I think he could benefit from grief counselling because even after all these decades, Christmas is bound to be a terrible time for him, especially when surrounded by all your children playing happy families.
If he's a low earner and doesn't contribute much to your joint outgoings, that's a real imbalance. Although he may feel he's onto something good, financially, some men might feel quite worthless being 'kept' by a strong, financially stable woman. Maybe these outbursts are pent-up frustration with himself compounded by his grief.
Paradoxically, even though he's onto a good thing money-wise, he may feel you control everything (I know this sounds irrational) and it's his way of taking some control and being 'more of a man'. I don't know how his daughter died but maybe there is some misplaced guilt or blame there too?
You both need to sit down and have a sensible discussion about how his reactions are affecting you.
The other possible issue is dementia. One of the first signs can be mood changes. One of my parents died from dementia and they changed from being a placid, reasonable person to someone aggressive and downright unpleasant. Are there any other signs he may be on that road?
I'd be very worried if I were him because if you die first, where does he go?
He'd have to rent for the rest of his life- and how would that work when he only has a state pension? Does he have an occupational pension?
I know this is not your problem, per se , but you have contributed to it by not having an honest conversation about the future and his security. Presumably your Will leaves your assets to your children?