I don't like it here and want to run away?

[Ellasa]

Hello, I'm a 17 year old girl and I'm turning 18 this December. My father and my mother both died. One when I was 14 and the other when I was 16. So I now live with my 27 year old brother (a doctor) and his wife, and i don't like living with them. I used to love my brother with all my heart but he's changed quite a bit. I've never really liked his wife. They yell at me a lot, and they try to act like my parents. They won't let me go out with my friends or go on certain websites and yell at me a lot if they find out I've been going on them (Facebook, twitter and other social networking websites) I don't get along with them at all! I've always been a "sad" girl but I've gotten mad and sad ever since I started to live with them! So when I turn 18 Ive made up my mind and I want to move out. But my brother and his wife won't allow it. I don't know what to do. Even if I do move out I have no idea where to go. They won't let me go to a college that isn't close from home and they won't let me live in a dorm. Even though I have no idea how to get away I know I can't stay there! I don't want to stay there. It's horrible there. (they don't abuse me) I don't feel Like I fit in there and I don't like being with them. I'm thinking about running away but don't know how to or where to go if I pull it off. Someone please help me I don't know what to do.