My question involves civil rights in the State of: Pennsylvania

I'm 21-years-old, and my girlfriend is 19. I wasn't entirely sure where this should go so civil rights seems like my best option. We were caught partying in early January, and since then her parents have been doing a wide assortment of morally questionable and outright disgusting things trying to intimidate her and make her play their game the way they want her to. First, they put up a moving billboard in front of one of their businesses with her first name on it to publicly humiliate her; I believe they don't even have a license to put up this billboard in the first place. She is only living with them because she has no options, and both of her parents constantly berate and fight with her when she goes out of her way to avoid them. She has been staying elsewhere when possible. They bought her a car for graduation, a car that she pays insurance and gas on, and they've taken it from her repeatedly, the most recent time being because she left it somewhere else in a snowstorm that she wouldn't have made it home in. Her father called the police and if she doesn't get the car back to their house by tomorrow, a warrant will apparently be issued for her arrest. I know a lot of this isn't necessarily a legal issue but I'd like to know if there's anything that can be done to make it stop.