For Nicole Scherzinger, life in the Pussycat Dolls was not purr joy.

Despite taking center stage with hits like "Don't Cha" and "When I Grow Up,” the singer reflected on the “overwhelming experience” as the group’s frontwoman.

“I’m really proud of the music that the Dolls made, and I’m very proud of the little mark that we made with our group,” Scherzinger told the U.K. newspaper The Times in an interview published June 27. “But it was very difficult, because I was really learning about myself along the way."

And she attributes a lot of the stress from that era to the grueling schedule she and her bandmates—which included Melody Thornton, Carmit Bachar, Ashley Roberts, Jessica Sutta and Kimberly Wyatt—endured.

"It was such a difficult time, struggling and battling your own demons and issues and always being on the road, and they never allowed sleep in our schedule,” Scherzinger explained. “I mean, it was just a recipe for disaster, to be honest with you."

It’s a work schedule the 45-year-old says couldn’t exist today.

"They have rules set in place,” she noted, “and, you know, it’s more of a woke community now. But it wasn’t like that when we were doing it. It was just kind of like, ‘Work them to the bone until they’re passed out.’ It was just hard for me to sleep. I always had sleeping issues.”

Scherzinger, who has in the past spoken about her battle with battle with bulimia, also said her time with the Pussycat Dolls, a group that was inspired by an existing Los Angeles burlesque dance troupe, accelerated her insecurities about her body.

"A dancer’s body is the instrument; it’s beautiful," she said. "But I was a singer first. It was difficult for me in the beginning because I didn’t feel comfortable in my skin.”

E! News has reached out to a rep for Pussycat Dolls founder Robin Antin for comment and has not heard back.

While Scherzinger, who joined the pop group in 2003, has had a successful solo career since the band split in 2010 and even won an Olivier Award for her role in Sunset Boulevard earlier this year, she has reunited with her fellow Dolls in recent years. In 2019, several members of the group and Scherzinger performed for the first time in a decade and released a new song in 2020.

But a reunion tour was postponed due to the pandemic and later canceled amid an ongoing legal dispute between Scherzinger and Antin, who is suing her for alleged breach of contract in 2021.

“The lawsuit came out of nowhere," Scherzinger explained. "It was a complete shock and disappointment and heartbreak for me. But I’m not a victim; I’m a victor. And I stood my ground. I knew where I stood, which is why I responded with eight counter-claims. But, you know, I’m hopeful for the future. I’m very hopeful.”