That's hard going. Think my brother-in-law is going that way a wee bit too. And it's really difficult to know what's the best way to deal with it. Of course it's a shit situation for everyone and we're all pretty miserable so that gives people who are feeling lost an easier slide into looking for conspiracies, cover ups and what have you.
Even despite the fact that for years politicians like Obama have mentioned how the science has suggested it was always a matter of 'when' not 'if' we get hit by a pandemic. But some people will just look at that as more evidence about how it was a plan all along :/
I have no idea how to deal with it. For ages I've just tried to ignore it as he's a bit stupid (he's a flat earther too ffs) and a compulsive liar, but I love him. It really blew up the other day for me as I finally took him on with it all. Bit of a confession this, but thought I may as well be honest as I can't be the only one losing their shit with family. He cycled round to see me and we chatted outside and he went full on 'they can't isolate it or prove it exists, it's a casedemic, it's a plan to reduce the world population, the hospitals aren't full'. The amount of contradictions to his own arguments was insane, but he simply can't see it. Got more and more heated when I pointed out the simple flaws in his argument, to the point where he decided to get very personal and say something incredibly insulting about my fiance (she's been posting things on Facebook that counter all the anti-vax nonsense) and I lost it. Kicked his bike and slapped the side of his head.
I really should't have done it, and I apologised within a minute saying he can't talk about my missus like that...but I'm fed up of him putting my parents at risk (he goes round for a brew) and the insult to my missus made me lose it. I didn't hurt him, he was wearing his helmet and he barely flinched, and I'm not sure I wanted to hurt him either, just was raging about it all. Not really proud, but the frustration was driving me mad. Not gonna lie, it lead to a bit of a mental breakdown for me personally for the rest of the day! All my worries and anxieties came flying out, and 30 mins of my brother calling me a sheep, spouting dangerous nonsense and then insulting someone I love....yeah. Exploded. Fuck this whole thing, fuck these conspiracy theories idiots. My brother included. I hate that I'm so resentful towards him about it.