The Disney star reveals on April 22 why she had an emotional breakdown and admits she feels horrible for hitting her backup dancer. Will you watch?

Demi Lovato, 18, wants to “open the eyes” of her young female fans. Demi sat down with ABC’s Robin Roberts to explain her life-long battle with an eating disorder and why she resorted to cutting herself. The starlet has spoken with fans since leaving rehab at Timberline Knolls, a leading residential treatment center in Illinois. But April 22 will be the first time she’s gone in depth about her violent altercation and leaving the Camp Rock 2 Tour.

“The real reason why I’m sitting down with you is to open up the eyes of so many young girls, that it doesn’t have to be this way,” Demi says. “[Cutting] was a way of expressing my own shame, of myself, on my own body. 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 goes on to say that she went through a downward spiral — and hit bottom when she attacked her backup dancer Alex Welch.

“I literally was so emotionally whacked out that I took it out on someone that meant a lot to me. I take 100 percent, full responsibility. I feel horrible. [She] was my friend.”

Demi adds that she’s had a “a really unhealthy relationship with food,” and it caused her to develop a horrible eating disorder.

“I was performing concerts on an empty stomach,” she says. “I was losing my voice from purging. I was self-medicating. I was not taking medication for depression … I developed an eating disorder, and that’s kind of what I’ve been dealing with ever since.”

But Demi appears to be making her comeback and we are behind her all the way!

Tune in this Friday to 20/20 at 10pm for the interview!

— Chloe Melas

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