Partner seems paranoid about me going outside and I'm worried he has a mental illness

So, I've been with my partner for over 20 years and we have a 12-year-old. He used to go to work at an office, occasionally see friends, and he could be abrasive at times, but it wasn't an everyday occurrence. But something has changed.

In March 2020 due to Covid, his office started work from home, and he's still doing so today. In this time, he has gotten more verbally abusive, controlling, and I'm at the point where I'm thinking he has some kind of paranoia combined with narcissism, and I'm 100% sure our relationship is an example of coercive control. I just wish I opened my eyes to it sooner because I'm piecing things from the past together and I see it.

During Covid, he used to try to stop me from going for walks for fear of me getting sick. He'd say "just be patient, wait it out." He was convinced even me walking on a quiet street a block away was risky.

Now, the issue isn't Covid. He claims it's too unsafe in the world due to ICE, violence, whatever happens to pop up in the news. He's saying I shouldn't go out walking alone.

He's left the house a total of 4 times since 2020, only due to needing to mail things for work. He's lost contact with friends and all he does is work or play video games.

I go out and walk, go to appointments, but I rarely get to go out and do anything alone.

He's gotten intolerant of me doing anything, even when he's working. We live in an apartment so he works out of the living room. I'll go down the hall to clean or do laundry, and he'll say I'm being "cagey" or "you're trying to be isolated, you don't want to be part of this family."

He's constantly, constantly pushing a narrative that I don't need time alone and I'm beginning to think it's part of him wanting to control me.

I actually went out to the ballet with a friend last month but told him I was going to a writing workshop. I had a wonderful time, but the next day he accused me of cheating on him out of nowhere.

Today was ridiculous. I went to take the garbage out and he started asking why I needed to do that, and accused me of taking it out 3 times yesterday. Which I didn't. And then he said I'm making up contrivances to go outside and that the world isn't at a place where it's okay to just be outside wandering around!

I also should say he's convinced our son that he doesn't need to get sun or go for walks, either. This week he said "the people on the international space station are up there for months and don't get sun and they're fine."

Does this sound like a mental illness? He's trying to convince me I'm wrong, in fact, he frequently says "are you okay, do you need to see someone?"

Meanwhile, framing my wanting to go on a walk as not wanting to be part of the family, being a bad mom, and trying to shame me in front of our son, calling me "like a dog who has to go outside and pee on the grass."

I'm livid I've let this go on, and I just don't need where or to whom to turn to, let them know this has been going on. My son does school online, too, so he's isolated.