It takes a while for Demi Lovato to drop her first F-bomb. She keeps it under wraps at the offices of SiriusXM Radio, where the curvaceous singer is hovering placidly in the land of PG, wearing a demure black dress that covers even her collarbone, and touting her new album, Demi. But, you know, eventually things get real. We're in a black Suburban on the way to an album signing at a mall on Long Island, when the 20-year-old Lovato mentions her mother's estranged late father, who "turned out to be a gay hairdresser. I love that," she says. "You have to be a brave motherfucker to be able to come out in the Sixties."
And just like that, the Disney princess facade is, well, fucked. Which is as it should be. From the jump, Lovato's trajectory seemed both charmed and predictable. A child-pageant past primed her to land a role as one of the "friends" on Barney & Friends when she was seven years old, which led to a star turn in a number of Disney TV movies and shows, which of course led to the release of several albums, a relationship with Joe Jonas and a cemented spot in the tween obsession mill. But if Lovato feels a curse-worthy affinity for a man she never met, it's no doubt because she's had her own battle "coming out" as a pop star with problems. Not content to merely be the edgiest one of her Disney cohorts, by the time she went on tour with the Jonas Brothers in the summer of 2010, she had stopped eating regularly, taken up drinking, drugging, and started purging. After she took a swing at one of her backup dancers, her family insisted that she go straight from an intervention at their home in Texas to a rehab facility to deal with her emotional issues. She thought she'd be there 30 days, but ended up staying three months, through Thanksgiving, Christmas and New Year's Eve. "Celebrities do have luxurious options, but my parents were like, 'No, you're going to learn something,'" she says. One thing she learned was that she is bipolar, which was not unwelcome news. "There were times where I was playing for thousands of people, and then I'd get on my tour bus, like, 'Why can't you just be happy? What the fuck is wrong with you?' It was a relief to be like, 'Oh, my God, it's not me, it's my brain.'"
These seem like exactly the sort of revelations a Disney darling would not want to mention, like, ever, but Lovato decided shortly after entering rehab that she was going to go, if not rogue, at least public: "My parents were like, 'You have two choices. We can either just shut it down and not talk about it, or you can tell people what's up.'" Lovato went for the latter. "There was no hesitation, really. I opened up that gate."
This has meant tweeting about rehab and openly sharing the fact that she'd been staying in a sober-living facility (where she recently broke her leg because an ex-meth-head roommate didn't realize you couldn't polish the floor with Pledge). It's meant talking (and writing and singing) about her estrangement from her own birth father, explaining to Katie Couric that she remembers feeling fat at age three, and admitting that she was suicidal by seven. "The principal called my parents and made me sign this suicide contract saying that I would not kill myself," Lovato says. "They weren't expecting that so young." More than anything, it's meant putting herself out there in a way that actually, truly, honestly seems less about angsty rebellion or attention-hoarding and more about a process of self-discovery in which she has let her fans play a part: "I'm open with my issues, my sense of humor is crude and raunchy, and I don't hold back."
The new album itself is the unabashed work of someone recovering from the process of recovery: There's some pop sass, but also a lot of lovelorn ballads and moments of emotional vulnerability. It's also a rebound from her misguided third album, recorded shortly after she left rehab, and inexplicably loaded with overtones of hip-hop and R&B. "I wanted to be like Rihanna. But I had to learn that wasn't me."
If being the first post-rehab teen queen is a calculated move on Lovato's part, it's working – Demi topped the iTunes charts in 50 countries. Tonight she'll celebrate the album's success by getting her 13th tattoo. (Did she ask her parents before getting inked the first time, at age 16? "Hell, no!" Were they angry? "Hell, yeah!") In a week she'll be starting her second season on The X Factor, where, unlike Britney Spears and L.A. Reid, she's returning alongside Simon Cowell, with whom she is charmingly able to dish it as much as she takes it. And right now, waiting in the bowels of the Roosevelt Field Mall, she's able to laugh about the weirdness of names ("'Demi' means 'half,' obviously. I learned that at Victoria's Secret") and tripping over cords ("Yeah, I'm a professional at tripping!") before being escorted to the atrium, where hundreds of teens fall into fits of apoplexy. As they approach, Lovato is gracious and calm in the face of sheer hysteria. "Oh, my God, she's everything," says one teenage girl, tears streaming down her cheeks. "She saved my life, literally."
Meanwhile, word arrives that her single "Heart Attack" has gone platinum. Lovato keeps smiling and signing. "I'm not a superwoman, and I can't do everything," she says. But life post-rehab is "not as scary as I thought it would be."
This story is from the June 20th, 2013 issue of Rolling Stone.