How to deal with my stepmom and my lying half brother?

Ok! So I have a spoiled little 6yr old half brother that gets what he wants and does whatever he wants. My parents were divorced and I lived at my moms house most of the time... Until she had just barely ped away on may 22, 2011. So now I live at my Dads house (which I hate) it's not my dad that I hate, it's the way my stepmom treated me by calling me names and telling me I'm worth nothing and that I'm gonna end up like her loser brother that's in prison. On top of that, I have a half brother that my stepmom and dad had. He takes after my my stepmom.. Mean, demanding, and a name caller. He lies to his mom and tells her lies saying I punched him or I hit him or broke his toy, I get blamed for everything and then she believes it. Therefore, I have no privileges what so ever and I'm not trusted! No phone no computer no nothing! Although, I do have an iPhone nobody knows about..... My family is a mess. Funny cause, since I'm the oldest, everybody points to me, except my 10 yr old sis, like my bestfriend! I love her cause she's not liar and knows that I'm not one and that everybody gives me a hard time.... I'm really stuck here. Please help... I wish I didn't live there but there's nowhere for me to go... :(