I have to agree with some previous posts, I don’t think this is purely down to depression or related things. The way he’s behaved to you is out of order, whatever the reason, mature adults who have spend so long together should be able to communicate without abuse.
Can I ask or presume that much or most of his behaviour towards you has been behind closed doors & others weren't there? If, as I suspect this is a yes, then you could be looking at a particular kind of being/behaviour. Someone else did mention “personality disorder”.
This sounds a lot like what I’ve been through (apart from not having another place/home to go to/accused of infidelity). I came out of a 30 year old relationship almost a year ago & have learned a lot, studied what I suspected. This had been awful/toxic for at least a decade, but we got caught up in son’s & daughter-in-law/small kids life as both adults disabled. We were almost bringing up Grandson & it was hard, plus my health went down the pan & I became disabled. I now believe he has narcissistic personality disorder(NPD) but funny enough he said way back he had major depression in early years & used to shut himself in bedroom for days at a time. When the nastiness/arguments started in later years, was almost always behind closed doors, because narcissists want to keep the “mask” on & for everyone to believe they are a “good person”, heard this often. They project their anger, emotional angst & failures (in his case, never held down a job for long) on to you, closest person to them. He also made out to his family & my son, how “difficult” I was, so it would deflect from him. Anyway, there is so much on this, could be here forever. There is a lot more around now online & on youtube about NPD.
Though I thought son sided with his Dad, he did tell me recently that when I became disabled/chronically sick about a decade ago, ex-partner couldn’t deal with it. He said I was the one who always sorted £ home, bills & more, plus working & he was annoyed this had changed. They are so selfish, like a child.
Anyway, hope you gain some ideas, hopes from people’s posts/answers. It will be painful getting through this, no point in sugar coating it.
There’s something about this site/page that makes you feel you can write about your issues & respond to others too. Don’t recall posting as much elsewhere ? Take care.