Demi Lovato was, as one of her addiction specialists puts it, “on the road to suicide.” At 19, she was publicly pretending to be sober but privately getting high of bags full of pills and eight balls of cocaine. She was also boozing hard. Demi was so wasted on her way to perform on American Idol in March 2012 that “I vomited in the back of the car service on the way to the airport [to fly to LA],” she confesses. Hungover for the entire performance hours later, she had hit a dangerous new low. “I didn’t care,” she admits. “I just knew that I needed to be high.”

That incident led to what her manager Phil McIntyre calls “the showdown of all showdowns.” He staged an intervention to save Demi’s life and got her whole team — managers, attorneys, agents and more — to agree to cut ties with her if she refused to get sober. “It wasn’t a matter of if they’re going to leave. It was, ‘They’re leaving,’” reveals Demi in her raw new YouTube documentary, Simply Complicated.

For years she had been torturing herself and her loved ones with empty promises to get clean. Now, faced with losing her career and her family, she begged them not to give up on her, smashed her cellphone and dunked it in a vase of water, cutting of all contact with her dealers and other bad influences. She knew she’d hit rock bottom. “It was the beginning,” she says, “of the process of surrendering.” This time, it worked.

Demi, now 25, listened, committed and privately got clean while living in a sober apartment for a year where she had to do chores alongside roommates, all while serving as a judge on The X Factor. Though she’d already made headlines at 18 for going to rehab for drug use, self-harm issues and an eating disorder (she also was diagnosed with bipolar disorder while there), it didn’t work: She says she immediately relapsed. “I was either craving drugs or on drugs,” she recalls, adding that she was sneaking them on planes and in bathrooms, sometimes in the middle of the night.

demi lovato

Demi attends The X Factor season finale press conference at CBS Studios on Dec. 17, 2012 in Los Angeles.

Post-treatment, while publicly promoting a sober lifestyle, she went on a two-month bender fueled with cocaine and Xanax “where I was using daily.” These are only a few of her shocking new confessions in the documentary. The “Sorry Not Sorry” singer confirms that years of being bullied led her to try drinking to be popular. Then, as a 17-year-old Disney Channel star, she began abusing cocaine. “She started doing the TV movies [like Camp Rock] and started doing drugs. She would come to the lot strung out and wired,” a source tells In Touch exclusively. Adds an insider: “No one wants to admit it, but there was a drug culture at Disney.”

Demi just couldn’t stop. Even after being admitted to a psychiatric ward because she’d downed half a bottle of pills, she kept using. She faked clean drug tests by using other people’s urine. She was so far gone, she went through about 20 sober companions. Her mom and stepdad wouldn’t even let her be around her little sister, actress Madison De La Garza, 15. “It’s embarrassing,” Demi now admits, “to look back at the person I was.”

The pop star finally got sober in 2012, and she isn’t ashamed of her dark journey. She’s opening up about it “as her way of giving back in the hopes of helping others with similar issues,” including her teen sister, says the insider. “Sharing her struggles with drugs, food and body-image issues, that’s all part of her recovery program. It’s the most honest she’s ever been because it’s the most confident and secure she’s ever felt. Those were the worst years of her life.”

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