Listen. People are just like you. You're no different. Most people are "afraid" I do this, all the time. As I'm walking somewhere I look stangers in the eye, smile, and say hello, how you doing, any type of casual greeting I feel like. Most people are to afraid to initiate contact.
Years ago I took a sales job dealing with the general public and most co-workers didn't last long. 6 guys would be waiting for a customer to arrive bitching and moaning about business being slow and then when the perfect customer arrived 5 guys would all go to the bathroom. See what I'm saying. I was the sixth guy. I had to mentally steel myself at first and in my mind, clap my hands and say to myself "SHOW TIME" know what happened? it got easier and easier to feel in control of the contact with others I had to deal with.
It's a simple exercise, look someone in the eye as they are walking by, smile a carefree smile and say "hello" or "hey how are you doing" and this is what will happen, you'll make someone who is feeling just like you feel better. They are no different than you. Live is about carrying a shitload of baggage that's depressing. Make the most of it.
Here is another one I've heard from a lot of people who had reached their end. "I didn't care about living or dying, so I went skydiving" This is liek a jump start tot he system. I'll tell you this find yourself in an ambulance being raced to the hospital and life is well worth living..... you're not living life, you're not dead and you're not alive.
I had a shitty job, I couldn't eat, I couldn't sleep at night, I was depressed, it was suggested I take medication. You know what I did. I found a new job that required physical exertion, once I did this, I quit my job, started a new job, it was exhausting at first and I was forced to eat more, when I was done with work I went home and you know what? I ate again and I fell asleep. You know what happened after several months. I felt better about myself, I smiled more, I ate more, I slept better, I wasn't depressed, and I was more confidant. The end result I changed my life and I was making less more at the harder job than I was with the previous one.
Seriously, the people you walk by are afraid just like you. Say hello at first, watch their surprised reaction, don't let the person who is so surprised that it seems weird stop you, say hello to someone else, it's an experiment, just try it and look for results. As it becomes easier to say "hell" to strangers start saying "hey, how are you doing, it's a great day isn't it?" and smile a goofy grin. It puts people at ease and they will smile back. The power of a smile is amazing.
For all the things you beating yourself up about. If your apartment is a mess you have to get up off your own ass and clean it. Life is about doing for yourself and you seem to think that you're entitled to the happiness that others are finding because they are interacting with the world when you are not. If you don't feel like going out. Go out. While you're out say hello to people you do not know. I could suggest you burn your thumb with a lighter but saying hello to complete strangers confidently is much less painful and actually much more easier than you'd think. If you need a mental prompt to do so, simply say to yourself, "show time" and step up to the plate and live your live.
You know you're wasting your life because you're not happy. You're not supposed to be happy wasting your life away between being alive and not being alive.