Let's say you theoretically won £1,000,000 or €1,000,000 - not the silly jackpot figures (1 in 128,000,000 odds which are… beyond pathetic). At least with the smaller amount it halves those odds but let's say you got that.
You can't stay in an expensive country - so UK not chance of buying a place to be on your own - even flats can go for £450,000 plus the stamp duty, solicitors, etc and then you've got hefty annual service charges and insurance to pay for eternity.
I'd go to Spain and try and get a 1/2 bedroom flat (max would be around €280,000). Buy a cheap car outright to do errands in and that solves your own space/privacy without blowing the load.
Here's the biggest problem. Let's say you have a void (a partner left after years) - money ain't doing SHIT to resolve that. And copes like buying sex or other stuff just isn't for everyone (I'd hate that shit) and even if you did - it's just going to blacken you even more.
So you've got the time, own place and you can do your errands and go to the sanctuary and help out (if you want). Would it be better than your current situation? Definitely. Does it change your autistic, neurodivergent brain? NOPE.
It's really a case of it would have to happen to see how things would change - anxiety would go down due to a roof over your head and money problems and no you couldn't go on lavash spending sprees as the money won't last.
It's so ironic that the only way to have your own place nowadays is to either win the lottery or get inheritance/family money. I don't know anyone in the UK who managed to buy a place without their parents chipping in somehow - some even got high placing jobs due to nepotism. It's a fucking mess.
And no I wouldn't give away any large amounts - this draws WAY too much attention to you - if it was say €1,000 and you did it very rarely then you don't draw attention. If you make a BIG donation of €10,000 you have a problem (money laundering rules come into play) and people will talk about you - you just put a target on your head. It's horrible to do but if someone is getting annoying and asking questions you just say you work in finance or something plausible or don't answer at all.