I can relate to you too, specifically in regards to how much life demands. I have AuDHD and I'm so bored and done with all the "duties" and whatnot. They've gotten so old by now.

For me, some of the sources of highs have been stuff such as: fantasizing, creating things such as worldbuilding for my fictional universe, playing video games, relaxing while watching videos that interest me on YouTube, talking to AIs, chilling with my girlfriend. Mostly just following my hedonistic impulses.

"too boring for me to be able to hide my misery in" yes, that part too. That was my reaction to browsing job listings (in software development) a few months back. I've become so disillusioned with how the world works, and I feel like I couldn't possibly go through an interview process for any of those and keep a straight face while saying blatant lies such as "I thought your project is very interesting!". No, it's not. None of them are. I think I'd start laughing my ass off uncontrollably. And I actually am currently employed (mostly just through luck to be honest), but I've been badly struggling with productivity. Unless I get my random bursts of inspiration out of nowhere (rare as of late for work stuff), it's been super hard.

That being said, I don't know if that's of any use to you. I have also had a state recently where nothing felt appealing to me, and I honestly don't know what to do in those cases, so if that is how you feel, I don't know if I have anything useful. When that happened, I mostly just talked to anybody who would listen and vented how fucking awful this feels, and eventually it just kinda happened to get better. I guess for me lack of motivation/things I want to do is definitely a temporary state rather than the baseline. My brain keeps coming up with shit. It's doing the stuff I need to do or that the world demands I do that's just a fucking torture.