Ward End, I'm really sorry you've feeling so desperate and suicidal. Thing seem so tough and overwhelming for you just now. Given your upbringing and toxic family situation I'm not surprised you've gotten this low.
What advice could I give you? I would really suggest you look for some sort of outside help. How about starting with seeing your GP for some anti-depressants, or a walk-in clinic if you don't want to see your local GP? As well as contacting the Samaritans, who can lend you some moral support? Or anybody else you know and respect who would be willing to listen to you?!
Your family situation is just keeping you trapped in a situation where you just can't progress. For goodness sakes, get yourself out of the family home, and away from your father. And as for your mother, the clue is in the name- she is the adult, you are her child. It's her responsibility to look after you, not the other way around. Your assuming resonsibility for her is wrong and is bad for you. Leave her to find her own feet, it's not your job. Really, it is not your job.
You are really young, don't throw your life away. Your life has deep worth and value, and you need to find a way to value yourself.
In the meantime, maybe you could try homeopathic Aurum Metallicum, which is for suicidal depression. You can PM me if you like, for any more details or anything.
I've been on anti-depressants for a while, well on/off for a number of years. I haven't spoken to the Samaritans yet. I'm reluctant to speak to them, I don't know why but I just feel like speaking to them on the phone. Perhaps I can guess what they would say, the predictable stuff like 'you're valuable, don't kill yourself' (which I appreciate, don't get me wrong for all of you on this thread who have said that).
I know what all the rights things to do are, like get a job, leave home etc. I'm not clueless. It's just that I don't even feel the motivation to get to those points. My feeling for death is far stronger at the moment.