In a new interview with People Magazine, Mariah Carey has opened up about her struggle with bipolar II disorder, which is defined by the Mayo Clinic as "a mental health condition that causes extreme mood swings that include emotional highs (mania or hypomania) and lows (depression)."

The superstar singer shares that she was diagnosed back in 2001 following a breakdown, but for years lived in denial, which caused both her career and personal life to suffer. However, she says she's recently sought treatment.

"Until recently I lived in denial and isolation and in constant fear someone would expose me," she said in the interview. "It was too heavy a burden to carry and I simply couldn't do that anymore. I sought and received treatment, I put positive people around me and I got back to doing what I love -- writing songs and making music."

Carey says she's in therapy and taking medication to treat her disorder, and that the meds are working well.

"It's not making me feel too tired or sluggish or anything like that," the singer said. "Finding the proper balance is what is most important."

Carey says she chose to open up about her journey so that the stigma associated with bipolar disorder and other mental health issues can be lifted.

"I'm hopeful we can get to a place where the stigma is lifted from people going through anything alone," Carey said. "It can be incredibly isolating. It does not have to define you and I refuse to allow it to define me or control me."

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