Depiboy

I think I suffer from depression. Since 8 years, give or take. It started in high school, by isolating myself totally from my classmates (no speaking at all to any degree, with anyone), I avoided all sorts of communication with them. I don't know how it started, it just did. And since then it has gotten worse, I did not make any friends at the university, at all, I avoided people. I did not like what I was studying, at all (economics, major in finance and accountancy). I was not interested that much, however I kept studying, and reading, and was doing student jobs. I lived with several people together, but I could not befriend any of them. Well I was friends with my roommate, but I got jealous how a better student he was then me, and the friendship broke up. It sucks.
I wanted to be an astronomist, but I sucked at maths, my teacher in the high-school humiliated me in front of the class all the time. Great. I was reading books since I was 8 about astronomy, the universe, and such. To all that I'm poor, so I have to work for my living hard, in a job I do not like, in a profession I'm not interested. I've switched workplaces 4 times in 18 months, because I was always late, and my performance was just awful -I did not give a rat's ass about it at all.
I don't have a girlfriend, - never had one, no friends, nobody to talk to.
I've fucked up my life big time. I'm 26 now, turning 27 this December, and I'm really considering committing suicide. Life is a giant pain in the ass for me.
What makes it worse, I'm quite tall (190 cm), and I lift weights (My paragon is Schwarzenegger: thinking, career, and of course body) so when people ask me why don't I have a girlfriend I cannot answer...
What I like is physical pain. Not from damaging yourself but muscular pain, when the muscles work. This is the only time when I feel truly happy.
The ideal me by this age has graduated from the top university in the Country in physics, has a wife, and a stable existence, and a job he likes doing, and of course friends. None of these is there for me, I've ran out of time I think. Of course I can ask for help- I did, but what happened, or did not happen, cannot be changed. I've missed too much out of life, which made scars on my soul, scars, which will probably never heal... When I take a look back on my life, I feel... emptiness. Just plain emptiness, nothing more....