I agree with the poster above, that your sisters are not your responsibility. And I say that because I think you need to hear it many times, I know by experience that it's easy to take on responsibility for your younger siblings when your family have troubles. At some piont, as you say, they're going to see what your parents are doing and they will probably get hurt. I'm sorry, but you can't save them from that. The only thing you can do is being a good big sister. When you move out, you can still be a good big sister, but you can't watch over them all the time and protect them.
My suggestion to you is to talk to an adult, or in some way contact the social services. I think that both you and your sisters will need other grown-ups that can take care of you in a way that your parents doesn't seem to manage. I also want you to remember that you're not betraying your parents by doing this, your parents need help and so does you and your sisters.
Take care and I wish you all luck!
__________________
*
~*~Miiqa - by heart~*~
*
|