Well, I myself have never felt as you describe, but I can still only encourage you to hang in there. I don't really have a lot of friends, I've never had, I've never wanted to have. Of course people who are more social than myself will still find a lack of friends difficult, but just so you know that friends aren't absolutely necessary to enjoy life.
Try to find something that can get you through. Music, or a good, hilarious book. I've never been suicidal myself, but if I was, I bet Douglas Adams could get me through it.
Also, I know how crappy advice this might seem, but do try to talk about your problems with someone. If you are absolutely certain your parents won't listen, then at least someone at school. Heck, even someone at the local grocery store that you trust is better than no one. They will help you, if you just let them.
If you really feel cramped inside your home, why not take a walk? I don't know where you live, but a long walk in the woods always cheers me up and I know a lot of people who says it helps when they're down. Don't be afraid to try new things, you have a pretty unorthodox problem, unorthodox solutions may be required.
And well, probably a bit stupid this, but the one time I was really down, this song actually helped me a lot.
https://www.youtube.com/watch?v=tU1stt0okdM
And well...ska in general is great in getting you back up.
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