In her first televised interview since completing a three-month stint at a rehab facility in Illinois, Demi Lovato opened up to ABC's Robin Roberts about leaving her hit Disney Channel show, "Sonny with a Chance," to focus on her burgeoning music career – a move she deems important for maintaining her hard-earned health.
"For starters, I'm about to start working on my third album," the young star told Robin of her post-rehab plans, in an interview on Wednesday's "Good Morning America," that will air in its entirety on ABC's "20/20" on Friday. "And I get to express myself through music, which is what I love to do the most."
Demi, 18, has spoken openly about being bullied as a child, but said that until now, she's never felt "comfortable" admitting to the lasting effects the taunting had on her young life.
"I literally didn't know why they were being so mean to me. And when I would ask them why, they would say, 'Well, you're fat.' I was bullied because I was fat," she told the host. "And then a few months later I developed an eating disorder and that's kind of what I've been dealing with ever since.
"I was compulsively overeating when I was 8 years old," she added. "So, I guess for the past 10 years I've had a really unhealthy relationship with food."
Bulimia quickly took its toll on the teen queen's body – both mentally and physically – until the damage was too obvious to ignore.
"I was performing concerts on an empty stomach. I was losing my voice from purging," she revealed to Robin. "I was self-medicating. I was not taking medication for depression, and I literally was so emotionally whacked out that I took it out on someone that meant a lot to me."
As previously reported on AccessHollywood.com, Demi seemingly hit rock-bottom in the fall of 2010, when she admittedly punched one of her backup dancers on her tour with The Jonas Brothers, Alex Welch – something she told Robin she feels "horrible" about — prompting her friends and family to stage an intervention.
"They sat me down and said, 'You can't live like this. And the only way that you're going to get the help that you need is to go in-patient to a treatment center,'" she said. "And that's exactly what I did."
The former "Camp Rock" star also revealed rehab was incredibly challenging, but that her younger sister, Madison, who plays Juanita Solis (the daughter of Eva Longoria's character) on "Desperate Housewives," inspired her to stay committed to her treatment.
"A picture of my little sister, on my little bulletin board, was one of the main things that kept me going," she said. "I just kept thinking, 'OK, set this example for your little sister.'"
See the entire interview with Demi on "20/20" on Friday at 10 PM on ABC.
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