Matthew, I'm glad that you're here. There are kind understanding people here. I've had depression and severe anxiety all my life. It's caused repeated failure in jobs and relationships. I understand the wondering "Why am I alive?" All I know for myself is there are moments when I get a break from pain enough to be there for someone else who's having a hard time. My life doesn't look normal to a lot of people. I often feel worthless. Now and then, I see something of value. I'm 20 years older than you, and still struggling since childhood with depression and anxiety. I also see people with lots of friends, with spouses, and feel envy. I had to learn, only in the past year or two, how to stop talking about my negative states to people who didn't understand.
You have value. You are needed here in the world. Emotional illness sucks. It's lousy and unfair. I hope that you're getting some kind of treatment. Keep coming back here and talk. There are people here who've had similar experiences. Wishing you healing and peace.