Hey Bradster! You are really in a tough position. Obviously, you're family can't help you, and obviously, you need help. So get the help somewhere else. I never knew the Salvation Army did treatment. That's fantastic, you should look into it! There are other programs, too, that offer a place to go, start your recovery, live and begin to learn to support yourself. You'll have to get out your phone book and/or look about online and get in touch with them.
Try not to be too mad at your parents. It sounds like they just totally don't understand and maybe have problems of their own that keep them from being good support for you. Good for you coming here and seeking a way out. We're pulling for you!
p.s. If I was living with my dad these past couple of weeks (I've got nineteen days today) and he was buying me booze and telling me not to worry about it, NO WAY could I have stayed sober. Don't kick yourself. But find some help.