I know most people will say you're too young to be worrying about this, however, I've lived through the same situation, so I can relate.
My advice.. Stay focused. I went hungry sometimes when I was your age. Neighbors gave us food and I'm forever grateful for that. The truth is, all the pain/suffering made me want to get out of that life and be my own person. It''s been more than 20 years, I'm now almost 40, professional, with a great life and have been making very good money since I finished college. I don't like looking back because it's painful, however it was that situation that made me the man I am today. Go to school, take out loans to pay for your education, it will be your best investment.Don't blame your parents for their mistakes, they're only human, just remember, stay focused, be proud, be smart, stay in school and become a professional.. everything else will fall in place.
Do me a favor, if you find this useful, save this address and 5 years from now write back and let me know how you're doing. I feel your pain, I relate to you, I'm with you buddy.