She said: “The more that people tell their story, the more therapeutic it becomes. Also, if I’m able to share my story and it helps someone, then I’ve done my part.

“My fans are dealing with some of the same issues. And if I am a role model, then I need to speak up … and be there for them.”

Demi turns 19 on Saturday (20.08.11) but is delaying her celebrations to attend Kim Kardashian's wedding to Kris Humphries.

She told Access Hollywood: “I’m so excited, Kim’s wedding falls on my birthday. So, it’s going to be my birthday and I get to spend it at Kim’s wedding.”

Demi plans to celebrate her birthday at a later date, and Kim intends to join her.

She added: “She’s going to come to my birthday party.”

The singer-and-actress has previously admitted she felt she was a bad role model before her problems came to light because young people looked up to her when her life was not as perfect as it seemed.

She recently said: "Kids used to tell me, 'You're my role model.' And I'd want to shake them and be like, 'Why?' "
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Demi Lovato admits she was a poor role model

Demi Lovato hopes her honesty about her personal problems will give her fans the courage to seek help