Trapped, what should I do?

I can't have a social life. My parents keep me trapped and miserable in the house. I've been this way for a couple of years now. I'm 15 and I think I should be going out like many other teenagers. I cry several times a day because I can't do anything. I don't think it's something I should contact CPS about because I'm just at home. Feels like I'm grounded forever. I have to sit in the house all day. I still have three more years to go until I move out. Until then, I have to watch my parents live it up and have fun with their friends. My parents are alcoholics. They have their friends over at least two times a week. I can't have any friends over. I can't even talk to my friends or go out with them. My parents don't even let me keep in contact with my friends online. They let my little sister and my older brother go out, but not me. I don't think it's fair because I've done nothing wrong. I don't really have any friends. Not even best friends. I'm bottled up because I'm always in the house. My parents' friend feel sorry for me because they always see me sitting around in the house. I'm losing a lot of my friends because it's hard for me to keep in contact with them. I can't even make friends because it seems whenever someone tries to get to know me, they back off because it's like what's the point in being friends with her when she can't even have fun? It seems that my parents take things that make me happy away. If I'm in my room for too long, they take my door knob and my TV away. If they suspect that I'm taking to my friends online, they cut out my internet. It's hard to get help because I'm so detached from the outside world. I've done nothing wrong, why make me so miserable? I do admit, I don't have a life. It wasn't a choice that I made. Even if I am out for an hour, my parents tell me to come home. They don't do that when my little sister and my brother is out. I remember my mom telling me that I was a mistake and my father didn't want me. They were going to abort me. Could that be it? I know it's not my fault. I can't seem to get help. How can I help them? My parents don't even trust me. I was ually hared by one of their friends and they didn't believe me when I said he did. So their friend still comes over and drink and stuff. I have to sit at home all day and despise the company. They care more about their friends than me. I always have to be the one taking care of the house while everyone is out and I can't go any where. My parents have fun at the casino and the only thing keeping me company is my dogs. They're the ONLY value I have. I ALWAYS have dreams where I'm in my neighborhood. Maybe because that's the only place I know because I'm always here. It's hard for me to dream about other places because I don't really know any other places. I always try to fly away from this neighborhood in my dream because I'm trying to explore new places. I can't fly very high though so my parents come out and drag me back inside the house. Then the hallway sucks me into my room. My parents are making me so miserable, I'm vulnerable to suicide and they don't care. I got the choice of suicide out of my system because I have ambition. I believe that it'll all be worth while when I'm finally move out. But what am I to do while waiting for that moment? I've suffered long enough. I'm young and I think I shouldn't be treated this way. What if I die tomorrow? What have I done with my life? Life is short. Everyone else is out having fun and living it up and then I'm dead not having done anything with my life. Who is to blame? Not me. My parents. What can I do now? I know my education is my ticket out of this ruthless life. That's why I'm doing very well in school. But what else can I work on? I'm afraid I might not be ready for the real world. I have poor social skills. I'm too bottled up. I don't have anyone to talk to at home. Only my dogs but that isn't really helping. Who should I call for help? What should I say? So many questions, but so little hope.