Demi Lovato has been through a lot of pain, even though she's only 20-years-old. In November 2010, she had to check into rehab for her mental issues, including self-harm and eating disorders. Demi is now opening up about how difficult the time of treatment was for her: "Treatment was so difficult at first, I remember walking around saying 'I'm in prison!' They needed to have those strict rules in order for me to understand how sick I was." ...