It wasn’t cutting, anorexia, or even bullying that sent Demi Lovato to rehab… Today, a Life & Style press release reveals that Lovato was seen doing line after line of cocaine at a party in North Richland Hills after a Neon Indian performance at The Granada Theater in December 2009. The press release further reveals the singer’s drinking and self-cutting problem, as well as her violent streak – as in, she punched one of her back-up dancers in the face.

Texas college student Brian Payne clearly remembers the night he spent hanging with Demi in North Richland Hills, Texas, where he saw her firsthand doing cocaine at a mutual friend’s house party on Dec. 28 last year. “She was doing line after line like a pro – and she was 17 at the time,” he tells Life & Style, recalling the wild party they attended after a concert by the band Neon Indian at the Granada Theater in Dallas. “I just remember her doing it as if she had been doing it for a long time. It didn’t seem like something new to her.”

Other insiders say that Lovato has also been turning to alcohol to help with recent troubles, which include the death of a friend and the awkward situation of touring with ex-boyfriend Joe Jonas while he dates Ashley Greene. Lovato is said to have kept up her habit of hard partying right up until she was taken to rehab.

“Demi’s been on a tear lately,” says an insider. “She’ll chug booze straight from the bottle.” Luckily for Demi, her mother and stepfather were quick to take action after they heard that she had punched a tour backup dancer in the face. “They overheard one of the dancers talking about it and freaked out,” says the insider. “They heard Demi was drinking, but the news that her partying was getting out of control shocked them – and they confronted her immediately.”

Lovato has also reportedly been caught on tape in what has been described as a booze and drug binge that shows the teen pop singer snorting cocaine according to a report from RadarOnline.

In the footage, Lovato can be seen snorting the drug through a rolled up bill, according to the amateur cameraman who captured the images.

A friend who witnessed the 18-year-old do lines of coke at a party in North Richland Hills, Texas, told RadarOnline.com: “Demi was belligerent, being slutty and doing coke all over the house. The guy who hosted the party shot multiple videos of this and what I’ve seen with my eyes, Demi is screaming, ‘F**k all of you, I’m famous, I don’t care what any of you think of me the whole world loves me.’ He shot her in the bathroom as she was finishing a line (of cocaine).”

Their report stated that though the site has not personally viewed the video, that they do have knowledge of the alleged tape being shopped around. This is bad news for Lovato and her career with Disney, and is the second accusation by a student who also claims that he witnessed Lovato doing coke at the same party last December.

Demi’s reps have been relatively tight lipped on the subject. When Demi was first entered into a facility, the announcement said it was for ‘physical and emotional issues.’ That could be anything… including cocaine.

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Images Via: WENN.com