Upvoted for posting about your real problems despite them being messy. It's harder than people realize.

At their parties I feel alien, trying to understand conversations about authors and theories I ought to have read about but didn't because I spent those formative years trying to not kill myself.

I can sympathize. It's easy to feel like you'll never catch up to people who had various advantages in the past. I think, though, that you can get yourself onto a path where you wind up blowing right past those people who you used to compare yourself to without really noticing. This is because the right path has intrinsic motivation rather than extrinsic, so you start forgetting to compare yourself to others.