Some people suggest cruel remarks from her longtime producer, Lukasz Sebastian "Dr. Luke" Gottwald, may have contributed to Ke$ha's insecurities.
"He has been verbally abusive to her and insults her and the way she looks, saying she's not pretty enough or skinny enough," an insider tells PEOPLE. "The abuse ultimately led Ke$ha to a bad place."
A rep for Dr. Luke refused to comment.
Fans also appear to be upset with the producer, and have come together to petition that Ke$ha, 26, emancipate herself from Dr. Luke and take back creative control of her music.
In October, the singer told Rolling Stone that she'd like her sound to evolve.
"I'd like to show the world other sides of my personality," she said. "I don't want to just continue putting out the same song and becoming a parody of myself. I have so much more to offer."
"It was kind of out of the blue," a friend of the "Timber" singer tells PEOPLE about the singer's going into rehab. "She's just as sensitive about her weight as anyone is, but not constantly talking about it."
Another source says it is the music industry that is responsible for Ke$ha's negative body image. "Being in this industry hasn't helped her issues, it's made them worse. But it's also finally made her deal with them properly," the source says.
Ke$ha will remain in treatment for her disorders for 30 days, and sources close to her say she'll be able to conquer her eating disorders when she's finished.
"She thinks this is important to get a handle on, and it's great she's taking the initiative before it becomes something more serious," a friend says, while another adds, "She's a strong woman. She'll put in the work and get over this."
If you or someone you know is struggling with a similar issue, please contact the National Eating Disorders Association at 1-800-931-2237 or http://www.nationaleatingdisorders.org/.
For more on Ke$ha's recovery, pick up this week's issue of PEOPLE, on newsstands Friday