It's the routine, that's doing this to you.
In your posts you keep mentioning that you can't do this, you can't do that. You cite that you're too old as the reason. Did the government pass a law around your area that says you've crossed an age threshold? Did you get an official notice in the mail?
No?
Then who made that decision? You did. I'm not trying to be harsh, I'm just trying to point out that living a life of regrets isn't the path to happiness. You already know this. So what's the solution?
There are two things that can really get a man down. Lack of passion, and monotony. When you have a great passion about something, monotony can take a back seat. It doesn't matter than you're doing the same thing over and over again because it's your passion.
It's usually very hard to realize one's passion. We aim high. It's not worth doing something if it's easy or if everyone else does it right?
Now I'm a lot younger than you are, so you have to take that into consideration. But I've felt the same feelings and I didn't want to pursue my passions because they were too hard and too long term for me to realize. My salvation came in the form of taking enjoyment of working towards my passions. I've no where even close to hitting my long term goals, but I work on them often. And it sucks. No short term reward. Sacrifice. But it makes me happy knowing one day I'll have truly achieved something I set out to do.
You are still young Mike. What you did yesterday has zero to do with what you choose to do tomorrow. It's a real sobering thought, but your life is ending one minute at a time. Every minute spent is a minute you'll never see again. It's been mentioned that your life revolves around the computer and head-fi. It's not that it really does, that's just the medium in which you've chosen to fill the empty void of being awake every day. Once upon a time I did that with video games and weed. I won't lie, it was a lot of fun for a long time. But it's so... sterile. There's no sense of achievement. That sense of accomplishment made all the difference for me. The other real difference was the social interactions I didn't even know I missed. It was only when I started hanging out with friends and people again did I realize how lonely I really was at that point in my life. We're very social creatures. Human contact is very important for our emotional stability. Sometimes it's easy to suppliment with the internet and these sterile forms of communication. I was very active in high school, and was very social. At first during this period of "social vacation" I felt relieved that I didn't have to deal with people except during work. But I swear after almost a year of waking up, going to work, going home, smoking up, playing video games, going to sleep, rinse and repeat; I don't recall any human contact outside of a handshake that entire time. But the first time I actually hugged someone after I gave that type of life up, man it felt magical. I didn't even know what I was missing. I didn't even know I had those contact needs.
I know I sound like some dumb motivational poster, but realizing these things are what put you into gear. Your posts reek of sincere regret, lonliness, and longing for something you don't have.
Identify those things, and work every day to do at least one thing to achieving something on that list. It doesn't have to be huge, just one thing.
Oh, and go watch Fight Club. If you really get the meaning in that movie, it will motivate you in strange ways.
I can't claim to have been through half the things you have been through, but I know I have a unique perspective on things. While I was figuring my life out, I thought about this very subject for months non stop. If you ever want to talk, just pm me.