You might expect a lot of glamorous footage of Demi Lovato in the new YouTube-exclusive documentary that she co-produced — and you won't be disappointed. She's often shown in flattering light, in slow motion with perfect hair and makeup. But there's also a lot of ugly stuff, too.

Lovato spills the beans about her years of drug abuse, her eating disorder and even the time she angrily punched one of her backup dancers in the face. She discusses being bipolar, says she's still in love with her ex, Wilmer Valderrama, and that she constantly worries about what she did or didn't eat.

"Demi Lovato: Simply Complicated ," which airs on the video platform starting Tuesday, is a combination of a Barbara Walters special and an infomercial for Lovato's new album. It's a weird, sometimes uncomfortable, 78-minute fusion of artificiality and honesty, but Lovato's charisma ultimately pulls it off.

We see her suggestively sucking her thumb while stretched out on a bed in her underwear and giving us a come-hither look in wet hair, but also hear about a cocaine bender that ended with her in a psych ward. She admits drinking so much one night that she threw up on the way to a crucial performance for "American Idol," a gig she eventually did very hung over.

"It's embarrassing to look back at the person that I was," Lovato says in the film, directed by Hannah Lux Davis, who has directed music videos for DNCE, Nicki Minaj, Ariana Grande and Lovato, among many others, but is making her debut here as a full-length director.

The unrated film is the latest in a wave of star-driven music documentaries airing on streaming platforms that includes "Lady Gaga: Five Foot Two" on Netflix, a short feature on Apple Music about Pink's new album, "Clive Davis: The Soundtrack of Our Lives" on Apple and Katy Perry's four-day livestream in partnership with YouTube.

Structured chronologically, "Demi Lovato" uses old footage and photos to examine Lovato's rise from a bullied girl who was fascinated with death to a Disney princess on "Camp Rock" struggling with her squeaky-clean image, to her life today, as a sober music superstar who dates men and women, using online dating sites to find potential mates.

"I've learned that secrets make you sick," she says.

We learn she considered Shirley Temple's career a template for her own and was so disliked as a girl that a petition signed by schoolmates made the rounds requesting that she kill herself. We learn she first did coke at 17, faked drug tests and that she might not be over loving Valderrama, her boyfriend for six years.

"I think my heart's always with Wilmer. I think it was with Wilmer, I think that it is with Wilmer and I think it will be," she says in yet another moment of refreshing honesty. "I do have moments where it's late at night and I'm lonely and I wonder if I made the right decision." (Valderrama appears in footage but is not interviewed.)

Lovato's surreally beautiful voice is the soundtrack, whether it's featured in a slick, camera-ready video shoot or with her eyes closed, makeup-less and with her hair tied up, belting out songs in front of a microphone.

Viewers find out that she looked up to Amy Winehouse — both for her talent and, unfortunately, for her thinness — and that Lovato can be really witty. (She can also belt out a mean whale call when asked.)

There's plenty of honesty but bills have to be paid and much of the film serves as a commercial for the album she just released, "Tell Me You Love Me." Of the 12 songs featured in the documentary, seven come off the new CD, including "Sexy Dirty Love" and "Sorry Not Sorry."

This fusion of commercial with contrition doesn't always work but it's surprising how much brutal honesty we get between shots of Lovato working out in a light-streamed gym or suggestively lounging in her frighteningly white kitchen. Hey, it's complicated. Like Lovato.

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Online: https://www.youtube.com/watch?v=ZWTlL_w8cRA

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Mark Kennedy is at http://twitter.com/KennedyTwits