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Demi Lovato was in a very bad place three years ago before she finally sought help and went to rehab. How bad?

The "X-Factor" judge, 21, said she would "smuggle" drugs onto airplanes because she could only go so long without a fix.

"With my drug use … I couldn't go 30 minutes to an hour without cocaine, and I would bring it on airplanes," Lovato told Access Hollywood earlier this week in a sit-down interview.

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"I would smuggle it basically and just wait until everyone in first class would go to sleep, and I would do it right there. I'd sneak to the bathroom and I'd do it. That's how difficult it got."

The "Skyscraper" singer said she realized she needed help at 19 years old.

"I was going to the airport and I had a Sprite bottle just filled with vodka, and it was just nine in the morning and I was throwing up in the car. … When I hit that moment I was like, it's no longer fun when you're doing it alone," she added. "I think at 19 years old, I had a moment where I was like, 'Oh my God … that is alcoholic behavior … I gotta get my s*** together.'"

Related: Demi Lovato Opens Up on Bulimia, Cutting Issues

Lovato's mother, Dianna Hart, also spoke to Access Hollywood and admitted she was long in denial about her daughter's behavior.

"I suspected [she was using drugs]. It's like any other parent, when you see things, when you see signs … I think for a long time I was in denial," Hart said.

Aside from her drug use, Lovato also spoke about how at 8 or 9 years old she was "compulsively overeating."

"I would bake cookies and then eat the whole pan," she said. "I went to just completely starving myself, and that turned into throwing up," she said looking back. "It got really difficult [and] I would throw up and it would just be blood and it was something that I realized if I don't stop this, I am going to die."