At a moment of back-to-back career highs, Lady Gaga's mental health plummeted.

In her Rolling Stone cover story published Thursday, Nov. 13, the "Abracadabra" singer revealed she was previously on lithium and suffered a psychotic break during the "Joanne" world tour, which began in August 2017 but was later cancelled by February 2018.

The 39-year-old pop star said the crisis came after completing filming for "A Star Is Born," which later earned her an Oscar win in the original song category for "Shallow" and a best actress nomination.

"I did 'A Star Is Born' on lithium. There was one day that my sister said to me, 'I don’t see my sister anymore,'" she told the outlet.

The crisis also preceded her headlining set during Super Bowl LI in Houston in February 2017. A year later, she cancelled the European leg with just 10 remaining dates, citing "severe pain" from the chronic pain disorder fibromyalgia, according to ABC News.

"And I canceled the tour. There was one day I went to the hospital for psychiatric care. I needed to take a break. I couldn’t do anything," Gaga told Rolling Stone. "I completely crashed. It was really scary. There was a time where I didn't think I could get better."

Lady Gaga says 'I feel really lucky to be alive'

Gaga said she managed to recover from her mental health issues and now considers herself "a healthy, whole person." She added, "I feel really lucky to be alive. I know that might sound dramatic, but we know how this can go."

She credits her support system, which includes her fiancé, entrepreneur Michael Polansky, adding that "being in love with "someone that cares about the real me made a very big difference."

"How do you learn how to be yourself with someone when you don't know how to be yourself with anyone?" she added.

The pop icon recently landed seven Grammy nominations for her latest project, "Mayhem," including in the prestigious album of the year category. She told Rolling Stone the record was about rediscovering what she had lost and the "crazy" journey it took to "get it back."

This article originally appeared on USA TODAY: Lady Gaga reveals she filmed 'A Star Is Born' on lithium, which led to a psychotic break

Reporting by Anthony Robledo, USA TODAY / USA TODAY

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