This is a deep question that you likely won't find the answer to on the internet. You should talk to therapist and get this stuff out. Realizing it is the first step though.

if I’m not being useful to someone or supporting someone else or doing something worthwhile then I’m a waste of resources

Get that shit out of your head right now. You didn't ask to be here and you don't owe anyone shit. You are going to die someday and nothing will matter other than if you did what made you happy.

I don't know how you can change your perspective, but every life has inherent value. If something happened to you, it would really fuck up someone's day. If you have friends or family, it would fuck up several days for them. Even if you don't have friends or family, whoever finds you and/ or deals with it would definitely not enjoy the experience. So simply by staying alive and healthy you are improving the life of multiple people.

Also, you're probably having a more positive impact than you realize. If you help an old lady get her walker over a curb, that's a huge deal to her, you might not even register it. Same thing if you hold the door open for someone carrying something, or any other little thing. It doesn't even have to be an actual act of helping. If you buy groceries without being an asshole to the clerk, you are improving their day by reducing their amount of assholes per customer.

I don't go around thinking about my inherent worth, but whenever I'm feeling down I try to do something nice and savor how I improved someone's day. If it's in person, I look for their smile. If it's online, I imagine it. After I submit this comment, I'm giving myself a little pat on the back. I don't know if it helped, but I tried, and that's what matters.

Most of my friends killed themselves. I also thought that I was a waste of space. I went into debt to move across the country and figured if i couldn't put anything together, I'd off myself more quietly away from family.

Then I got a boss that actually valued my outside opinion. I got internal promotion and leveraged that job into a couple of strategic lateral movements. Now people lookup to me. It's weird. Recently I got a public honorable mention from Google. All this is cause I'm an asshole who refused to let the world near where I grew up, dictate what I should and shouldn't do.

Did I solve the fact that I tied my value to my contributions to society? No. But it turns out society is much bigger than the place I started and other cultures and societies think im useful. I still don't fit in and it's still lonely af. (I wish my friends were here so bad).

All that to say，they may not value you today but that reflects more about them than you. Today, I find great solace in reading books and learning ideas from people born hundreds or even thousands of years before I was born.

Don't give up. You may be helping a future version of someone like me or like yourself.

you is good enough