Demi Lovato has opened up about past demons, including her struggles with mental illnesses and addictions, in a long, candid and open interview with The Daily Mail.

The 21-year-old singer hasn't held back anything when it comes to talking about her darker side, to which she says she hopes to be "a beacon of hope for the next generation." Last November, Lovato released a book titled 'Staying Strong: 365 Days a Year,' a book designed to help her young fans get through tough times one day at a time.

"When you are no longer hiding anything, you don’t worry about what is going to get out," she admits. "I don’t care who knows about my life, and now that I am an open book a huge weight has been lifted off my shoulders."

Lovato believes that being bullied at a young age was what led to her eating disorders. "I’d just performed with an artist called JoJo; my friends were fans of hers but they didn’t get to meet her and I did. I felt uncomfortable saying that they were jealous, so I told myself that they hated me because I was fat. They were telling me I was fat, so it made sense – and that is what got programmed into my brain."

She then revealed to The Daily Mail that her addiction to painkillers came after they were prescribed to her after a car crash. "I liked the feeling they gave me – they sort of numbed everything – and I also liked the sneakiness of taking extra pills out of my mum’s bag without her knowing."

"Everything skyrocketed, which was awesome, but the negative side was that I thought, 'Right, I am working like an adult so I should be able to party like an adult,'" she admits.

Demi's father, Patrick Lovato, was suffering from his own problems as well. Her birth father was diagnosed as bi-polar and problems got to a point where she didn't want to be around him anymore. "He had started having delusions and I could no longer decipher when he was telling the truth and when he was lying. It just hurt too much, so in the end I cut off all communication."

The drinking and partying got to be too much and her mother firmly said that she needed to get help. Her mother had banned Demi from visiting her sister Madison until she sought treatment. "My life was a shambles and, although I had a lot of success, I was also very alone and miserable. I love Madison and one of the main reasons I wanted to get better was because I didn’t want to be apart from her."

These days, Demi is managing her own bi-polar depression with medication and tackling things one day at a time. On being diagnosed bi-polar, Demi confesses that she felt a sigh of relief. "I’d been living with this mania – moments when I was up all night writing songs, thinking I could take on the world, and also these deep, dark depressions, when all I wanted to do was shut the door and not talk to anyone. And that is why I had been isolating myself – to try to deal with the pain."

For more on her lengthy interview with The Daily Mail, click here.

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