Liking tweets is free. I'm sure he's paying that OnlyFans account plenty and you don't know it. Admit defeat and move on. Find someone who is only a fan of you.

so what? if that's the only thing "wrong" in your relationship, don't ruin your happy home over something stupid. just because he's on a diet doesn't mean he can't look at the menu

I don't see the problem. You shouldn't be any more threatened by onlyfans than you are the MCU or any other common form of entertainment.

These are two different FMLs. One is "My husband likes the tweets of a sex worker" which, like, so? Unless that sex worker lives in your town, why does it matter? Even if she did, does your husband know her? Does he even exist on her radar? Who effin' cares? The other FML is "My marriage called it quits a long time ago but we're still truckin' along". Divorce, if you can afford it. Have a frank and honest discussion about what to do to be able to co-exist without resentment if you can't afford it.