in my opinion, I think the best thing to do is reframe some of the thoughts you're having. If I'm missing important info, feel free to let me know. But based on your post it sounds like a big issue is shame of being financially dependent on others. As a disabled person who has to be dependent on others, I had to learn how to get over that. I'm assuming you're able-bodied, but, the economy is shitty, everyone's getting underpaid, especially younger ppl, and if you aren't able to find a job or be financially dependent, you're not alone.
It says way more about the economy and the greedy ppl trying to pay as little as possible than it does about you. Our parents, and our parents parents were getting paid much better in relation to cost of living than we are, and it feels like we're not really adults bc we've been unable to achieve the same milestones they did at our age. We can't compare ourselves to them.
This is not to say you won't find a job or be able to pull off independence. But sometimes it helps the depression spiral to be able to change your inner monologue from "I'm gonna a burden" to something like, "I'm gonna do my best, and maybe I'll find a job but if I don't, I still have value as a person and I will figure something out." I know it's cheesy lol but it's still true.
the unbearable mental anguish is a whole other thing unfortunately. I have no guesses as to what's causing that for you so I have no suggestions