I can't seem to be able to reply to posts for some reason, so here's my reply to yours below:
Hey man, hold strong! You have been hit with a lot of misfortune, but you still have an opportunity- that of going through this time with as much positivity as you can muster. I know there is not a lot to be positive about, but in a small way, you can still carry the torch. Your life is very physically and emotionally challenging, which are things that can be more or less out of your control.
However, what you have is your spirit and attitude. Think of these as the foundation you must fortify for all else to be reconstructed upon. With a little positive effort into these areas, you will be an inspiration for others around you, even in the most minute ways imaginable. It is likely you need to go through a period where the negative emotions need to rinse into your being and you will go through a very tough time, but this leaves you at a place where you can only go forward.
It will help to seek out some community by finding support from others, like in a support group. Also, look toward your doctor and don't be shy about getting counselling, but most of all, look for the spark within yourself.