"I remember every person who told me I couldn't do something or that I was ugly or too fat," she said in an interview with Seventeen last January. "People in the music business were like, 'You're never going to make it.' I see them now and I'm like, 'Ha!' "
But constant criticism of how you look can get to anyone, and on Friday the singer announced that she was entering rehab for treatment of her eating disorder. "I'm a crusader for being yourself and loving yourself but I've found it hard to practice," she said in a statement.
While the 26-year-old, who found fame in 2010 with "Tik Tok," talked about her healthy lifestyle in recent interviews, there were signs that she'd been struggling for some time.
In 2011, Ke$ha found herself targeted by bullies who criticized the way she looked in a bikini while hitting the beach in Australia.
But by April last year, she'd silenced the critics by revealing a slimmer figure in a series of pictures on Instagram.
"With my first record, I didn't realize how many eyes would be on me," she admitted in an interview with Metro. "I have to be stricter than I ever was before."
In June, she was featured on the cover of Self magazine, and talked about her diet and exercise regimen. "When I'm eating healthy and working out, it helps me stay sane and exude confidence," she said.
She insisted that she laughed at all the haters and negativity. "I've had so many people telling me, 'No, you can't do that,' 'No, you're not pretty enough,' 'No, you're not skinny enough,'" she said. "And I just had to be like, 'You're not stopping me. Get out of my way.'"
But by the time the video for "Timber," her collaboration with Pitbull came out in November, the singer was looking even skinnier.
In the wake of Ke$ha entering rehab, there has been speculation on social media that the singer's eating disorder was tied in with the ongoing battle over her career's future.
When the latest singles off her second studio album Warrior underperformed, fans launched an online petition to emancipate her from the person they felt responsible: her longtime producer Dr. Luke. The singer said in an October interview with Rolling Stone that she didn't have any creative control over her music.
"What's been put out as singles have just perpetuated a particular image that may or may not be entirely accurate," she said. "I'd like to show the world other sides of my personality. 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 than that."
Given Ke$ha's statement on Friday, when she emerges from her 30-day treatment, she'll have an even greater sense of who she is and what she would like to share with fans. As she said, she's learning "to love myself again. Exactly as I am."
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/.