Adam Lambert, Max Martin, Lukasz "Dr Luke" Gottwald, and Ke$ha on stage at the 28th Annual ASCAP Pop Music Awards at the Gran
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Since Ke$ha entered rehab to treat an eating disorder earlier this month, rumors have been swirling about what pushed the "Dirty Love" singer to the brink. Now her mom is speaking out.

"Dr. Luke had been telling her how she had to get in shape and lose weight and all this stuff," Pebe Sebert told People magazine. "She was exercising and dieting and ultimately doing everything she could, but not getting thin fast enough. And that's when she first became bulimic."

Dr. Luke signed Ke$ha to his record label in 2005 when she was just 18. He helped produce both of her albums, Animal and Warrior, but after the underperformances of her singles "C'mon" and "Crazy Kids," fans began to turn on her longtime collaborator. They created an online petition to "free" Ke$ha from Dr. Luke, and it currently has almost 10,000 signatures. 

Ke$ha's mom also told People, "Dr. Luke told a friend of ours he thought she looked like a refrigerator on her latest video, and could she please try to control her weight. After she went on a 14-day juice cleanse, he said, 'Thank God you finally got rid of the weight! We've all been talking about it!' So she felt like she couldn't trust anyone."

Dr. Luke's rep, however, is denying any involvement. "These statements and allegations concerning Dr. Luke are completely false. It is unfortunate that at a time Ke$ha is suffering immensely and trying to heal at a treatment center, her mother is taking this approach with the media. I give Ke$ha my utmost support and well wishes for a quick return to health."