I'm an idiot who didn't start getting this way until around age 19. Then it was just a roller coaster of caring and not caring, thinking and not thinking though now the memory of it kicks in almost daily at some point, always right at the point where I'm about to start taking action at last. I'll be 22 in a couple months.

I'm experiencing the exact same things as you, wondering what the point is, how to cope with the ugliness of reality (my default method is to simply reject it and hide away in fiction. I'm infinitely happier in fiction), and above all, how to live.

It's unbearably painful, and it's hard. It's empty and confusing. Any avenue seems fraught with emotional danger - wrongness, failure,

Uh, hi. As someone who writes and thinks way too much about the same problems as OP, and is way too dumb to find an answer when seemingly everyone else has...this effing nailed it. It's all about worth: my worth, the worth of my actions, of life, of anything.

Though really: being brutal is easy? I guess if it's aimed at a particular person, but in general...I find it almost impossible.

Also about purpose: it sure seems like almost everyone can find one. That's what troubles me, what am I doing wrong that I'm so paralyzed like this, so empty and miserable, that thought and shame arrest every attempt at action? Everyone else can just get on with things, why can't I (and OP, if you're reading this, maybe you feel the same way)?

However, what I think Wandering Soul and others are trying to get at is a balance between thinking and living. Just acting without thought ends badly, results in regret or even harm, like you pointed out. But thinking that never leads to action is frustrating, depressing, boring, empty and miserable. Or at least my experience of it is.