Man, I know this feeling... I don't know anything about you, but I don't think most people really understand the intensity of people who have the character to end up homeless or just in situations like this generally. Everyone I know who's been in a place like you tends to have a heighten experience of the world. Lows are cripplingly low and highs tend (where they exist) tend to be euphoric. People also used to try to convince me that I was wrong to feel the way I did, but I don't think I was wrong, I just experience things differently to others. I find it more odd how normal people are. Why would you not want to get addicted to drugs or alcohol? Why would you accept a normal life? Why wouldn't you want to die if you're not offering value to the world? I need to have intensity in one way or another or I don't want anything -- I would prefer to die. The fact you were a radio announcer suggests to me you might be similar because you're clearly not stupid or socially maladjusted, which in my experience is the other category of people who find themselves in a position like you.
At my lowest I was trying to drink myself to death. I wasn't quite homeless thanks to the support of family and friends, but weeks away if I didn't make changes. It took me a couple of years to pull myself out of that... You said something I relate to and still struggle with to some extent, "the world would be a better place without me". At my lowest I said this to myself constantly. I hurt so many people and offered so little value to the world that I knew objectively the world was better off without me. Those who told me I had value were clearly lying, although looking back I guess it was a nice lie they were trying to convince me of... If you're like me I think maybe the first step to get better is to ask yourself how you can bring some value to the world again? This can be as simple as feeding squirrels in the park or picking up litter from the streets, but you first need to give yourself purpose and a justification for living. If you can remove that thought telling you, "the world would be a better place without me" you'll find it's much easier to break any destructive cycles you may currently be in..
From there it's really just about taking small steps every day... Talking never helped me, but I'd be happy to talk more about your personal situation especially if there's something stopping you from finding a purpose and building your life back up. I know for some people there can be other factors at play which make recovery impossible. It's been 5 years now since my recovery and these days I'm quite content. It might also worth noting that I went from having practically nothing to being what most people would consider very wealthy in that 5 years. I'm saying this because if you told me this would have happened 5 years ago I would have put the probability of this being true at less than 0.01%. I'm not religious, but I do sometimes wonder if someone noticed that I'm trying to be better... Either way what matters is that things can improve.
If you want to talk, kypro2 [at]protonmail.com. If not, I really hope you figure things out.
If you're interested I found my post from 5 years ago btw, https://news.ycombinator.com/item?id=13146741 I was drinking heavily at this point and I think the week before I wrote this my parents had to call an ambulance after they found me passed out in my house after drinking a couple of bottles of vodka... Things got far worse after this though. My girlfriend of several years left me some time in January and I became too depressed and wrapped up in self-hate to care to keep looking for a job. I just wanted it all to end.