Maybe getting a hobby would be good, a good healthy hobby that u
really like. Like me, sometime when i am unhappy i would go to the
library and find some fantasy books and escape into their worlds,
or i would go and paint, which i find very mediative.
The important thing is not too brood so much over things you can't
control. Take things in your stride as it comes.
As for why people don't like to come into contact with you, well if
you are not able to behave decently of course no one will want
to.
Take a look from their viewpoint, they also have their own
problems, and you behave badly, of course they want to avoid you.
Would you want to be around such a person.
I always hold this line in mind whenever i feel like taking out my
frustration on others
Do unto others only what you want others to do to you.
Cheer up, no one
owns you anything but yourself. No one has a responsiblilty to
cheer you up. Don't even think about suicide, it is only a coward
way out and depending on your belief, how sure are you that suicide
is a good way to escape, maybe there is an afterlife, and life
there is worse than it is here 
then it will be out of
the frying pan into the fire.