Birthday girl Demi Lovato: A real comeback kid

August 20 marks a major milestone for Demi Lovato: It's her 20th birthday. To say it's been a wild ride for the one-time Disney kid is an understatement. The truth is, she's faced more personal obstacles than anyone her age should endure. But not only has Lovato come out "Unbroken," she has come out … on top.

In less than a month, Lovato will be going prime time as a judge on the newly revamped "The X Factor," for which she was hand selected by Simon Cowell. A lot of people wanted Lovato's job, but Cowell — who knows a little something about helping people achieve superstardom — took a chance on her. Now she's chumming around with fellow judge Britney Spears, playfully sparring with Cowell in the press, and potentially making or breaking the careers of aspiring singers hoping to follow in her footsteps.

"The X Factor" is only part of Lovato's recent professional success. Her single "Give Your Heart a Break" off her latest album, Unbroken, has become her biggest radio hit to date. The song, which has sold over 1 million digital copies, was certified Platinum last week. This year she's also performed on several shows, including "American Idol" and "Good Morning America," and was tapped to co-host the "Teen Choice Awards" in July. Later this year she'll be getting the "Glee" treatment. Series creator Ryan Murphy announced the show will be covering one of her songs during the upcoming season.

Things could have gone in a drastically different direction for Lovato, which sadly we've seen happen to countless former child stars. Two years ago, the "Sonny With a Chance" actress was battling serious demons, struggling with cutting, drug use, and an eating disorder. She's credited her stay in a rehab facility in late 2010 — during which she was diagnosed with bipolar disorder — with saving her life, and even decided to share her story in an MTV documentary called "Demi Lovato: Stay Strong."

It's her candidness about her troubles that has been refreshing — and helpful to young girls. In addition to spreading a positive message in her music (like "Skyscraper," which urges people to believe in themselves and stay strong), she's given interviews where she doesn't hide from or sugarcoat her past problems. "I'm not gonna lie. I was self-medicating," Lovato told Seventeen earlier this year. "I was doing things like drinking and using [drugs], like a lot of teens do to numb their pain." But her "stupid decisions" are in the past. "I don't drink, I don't do drugs, I don't throw up after my meals, I don't starve myself. There's nothing that I do that I feel ashamed of."

This month, she appears on the cover of Self, telling the mag that — although her eating disorder is a life-long daily struggle — she's learning to accept herself for who she is. "I used to feel my most beautiful when I was on the red carpet or at events or something where I'm all dolled up," she told the magazine. "Now I feel like the moment when I feel most beautiful is when I'm able to hang out with a guy without my makeup on or lay on the beach with no makeup on and not even worrying about what my hair or what I look like before I fall asleep. When I'm confident enough to show myself without makeup on, that's when I feel my most confident."

She's actually become happier letting people see her flaws. While she rejected being a role model during her younger, more troubled years — which she said caused her to lash out even more — it's something she's embracing now. "I don't think it does anybody any good to just hide something or cover it up or lie," she said on "GMA" in July. "The reason why I did it is because that's what being a role model is about. It's not about being perfect. It's about speaking about your issues and inspiring others to get help. I wanted to make sure that I shared my story with people so I can either help prevent them from going through the same things I did or help them get help."

Lovato has a lot to celebrate this year. Happy 20th to her!

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