I'm depressed, what do I do?

My parents won't let me go out because they don't trust me. They won't let me have a cellphone and they get suspicious if I'm on the internet for too long. It's like I can't have a social life. All I do is lay in my bed in the dark. I'm not suicidal, I just want to be happy. They let my brother do whatever he wants because he's their only boy. They said that I almost killed my mother and that they were going to abort me. They don't know what I've been through and it's like they don't care about my feelings. I was sexually harassed by one of their friends and they didn't believe me. Their friend still comes around, but he hasn't done anything since. This even had CPS involved, but they didn't do anything because they didn't have enough evidence. I have no friends. The only ones that truly matter to me and has been with me through it all is my dogs. And it hurts when they threaten to give my dogs away. I feel like I should be entitled to happiness. It hurts that my parents don't love me back. These tears must mean something otherwise I wouldn't cry everyday for no reason. I'm 17 years old and I've heard people telling me to wait until I'm 18. But what then? I don't know how the real world is. What do I do when I'm 18, where do I go? I don't know.. I'm so lost. I just want to be happy.