Demi Lovato Says 'Negative' Impact of Fame on Her Mental Health Caused 'Incident Where You Punch Your Backup Dancer'

Demi Lovato is putting it all out there.

In a cover story interview with Grazia US , the actor/musician — who co-directed the new documentary Child Star with Nicola Marsh — reflected on the "explosive" moments that came from the negative impact of fame on her mental health.

"I didn't realize that it would have such a negative impact on my mental health," Lovato (who uses she/they pronouns), 32, said of their experience with fame. "And unfortunately, sometimes that looks explosive, like an incident where you punch your backup dancer on an airplane or you overdose from heroin."

(In 2010, Lovato punched Alex Welch , a dancer on The Jonas Brothers tour at the time. The incident prompted the pop star to go to rehab. Lovato suffered a near-fatal drug overdose in 2018 and had three strokes and a heart attack in the hospital.)

The "Cool for the Summer" singer said that working on the documentary allowed her to have the opportunity to make amends for the way she behaved.

"Talking to people who knew me at a different time in my life was challenging because I wanted to apologize for my behavior," Lovato told the publication. "I wasn't the nicest person to work with at times because I was struggling so much internally, and I was under a lot of pressure."

They added that having conversations with Raven-Symoné and Alyson Stoner in Child Star was "really cathartic."

"They were so lovely, so incredible, and so receptive, and I was so grateful for that," Lovato said.

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In an interview with PEOPLE , the "29" artist opened up about their decision to make Child Star.

"This was just a story that I had been wanting to tell for quite some time," she said. "I've always thought about exploring the history of child stars, and also looking at different points of views and the perspective of what it's like to be a child star in today's day and age."

Lovato added that they have personally "been very, very honest in the past" and "demonstrated that vulnerability throughout my life."

"I've shared a lot with people, and I've realized that my experiences don't define me," she said.