My girlfriend is mentally disabled. What does the law say about her guardians' right to restrict access to her?

My girlfriend was found at a young age to be mentally incapable of caring for herself by the government. Her guardians (grandparents) receive a check for her every month to take care of her. They are very protective of her, and have taken away (or destroyed) all the cell phones she's ever had and run guys off with bullets. She is 19 years old and I think she should have the right to see me if she wants. What does the law say? Florida, United States