How Do I fix this situation? I cant talk to her because of her dad?

Um... how about simply not listen to your parents? You're 18 for christ sake, she's almost 17. Have her parents handcuffed her to a toilet or something? Its called TEENAGE REBELLION- defy your parents and enjoy your youth while you still can. Sneak out if you can't handle simply walking out of the house in front of your parents.