Is it normal that my girlfriend is 18 and we can't see each other?

My girlfriend turned 18 two months ago. Her parents are trying to make her hate me with no apparent reason. They just want her to marry someone else from their friend circle. But she doesn't want to. Now she is punished, no cellphone, no computer, they got her clothes, they took her parfumes, she can't go out, she stays locked, they beat her, let's just say she is in total isolation and misery like in nazi germany or soviet russia. They are always insulting her, even in front of me, say she is fat, ugly, stupid, coward etc. She can only call me from school from a payphone, we speak for a limited time, and she cries but does nothing about her situation.

I told her I will get her to live with me, I have pretty decent home, a car, a job, I live alone, we understand each other great, I said I will provide her with everything, even education. After all that, she won't come with me. But she is always crying and saying she hate them, but she doesn't do anything to change that. I told her I could call the police and get her out from that place. They hold her as a hostage. But she just won't. She promises that she will overcome her fear to confront them. But she doesn't keep her promises, like ever.

For me it's time to move on, I told her that, I wan't to live free, I wan't to see my girlfriend and speak with her, I have no communication after all with her. I just want to move on and find a brave independent girl. She even threatened me that she will suicide herself in her home and she can't take it anymore. But she have a choice, she is after all an adult, 18 years old. She can't see me because she is afraid and won't even call the cops, but she doesn't want me to see other girls either. It's been 1 month this way and things haven't changed.

Is that normal and is it normal for me to still be with her?

Can't see her, but can't see other girls either.