Preview Demi Lovato’s First TV Interview After Leaving Treatment Facility

Instead of keeping a low profile upon leaving her three-month stay at a treatment facility, troubled teen star Demi Lovato sat down with Good Morning America host Robin Roberts to discuss the myriad problems she’s dealt with the past few years, including cutting herself, living with an eating disorder and suffering from bipolar disorder. Watch a preview of their intimate sit-down below.

The 18-year old, who just announced she will be leaving her Disney Channel show Sonny With A Chance to focus on her music career (as well as her recovery), explains that her eating disorder began when she was relentlessly bullied by other kids. “I literally didn’t know why [the bullies] were being so mean to me,” says Demi. “When I would ask them why, they would just say, ‘Well, you’re fat.’ I was bullied because I was fat.”

The performer began cutting herself at age 11. “It was a way of expressing my own shame, of myself, on my own body,” she tells Roberts. “I was matching the inside to the outside. And there were some times where my emotions were just so built up, I didn’t know what to do. The only way that I could get instant gratification was through an immediate release on myself.”

Demi also recently revealed to People that she was diagnosed with bipolar disorder. “Looking back it makes sense,” she says of her diagnosis. “There were times when I was so manic, I was writing seven songs in one night and I’d be up until 5:30 in the morning. I feel like I am in control now where my whole life I wasn’t in control.”

Watch for Demi’s full interview on Good Morning America tomorrow and on 20/20 on Friday.