Avoiding the world, Losing myself

I've been a shut in all my life because I hate talking to other people. Never had friends growing up neither, just acquaintances. Now I cannot even look people in the eye, let alone myself. I was diagnosed with major depressive disorder and anxiety a few years ago. I feel like my body's on auto pilot these days. It hurts sometimes and I'll probably never have any of the luxuries normal people have. (friends, partner, etc.) sometimes I stare at the ceiling and think about why I'm such a failure. I think about all of my past failures all the time, when I fuck up talking to someone or accidentally stuttering over some words because the stress becomes too much. All I really think of now is 'why am I alive?' What was I put on this earth for? To suffer? I feel like an outsider in my own body. Like I'm in some sort of comatose state where I can see through my eyes but I'm not really there. I don't even know who I am anymore. I don't really feel the mental pain as much, maybe I'm getting used to it, or I'm just getting numb to it all. Every day just feels the same. I know I don't have it as bad as other people, and I should be grateful for what I have and that I'm just being selfish. Maybe I am, I don't know. I think I just want to be happy.