In a new People magazine cover story, Mariah Carey talks about having been diagnosed with bipolar disorder and where she is today.
Although she was first diagnosed in 2001 (when she was hospitalized for a physical and mental breakdown), "I didn't want to believe it," the superstar singer-songwriter tells PEOPLE editor in chief Jess Cagle.
Carey says she finally sought treatment recently after "the hardest couple of years I've been through" — years of professional upheaval, an E! reality show and romantic drama.
"Until recently I lived in denial and isolation and in constant fear someone would expose me," she says. "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."
One of the most successful singers of all time, with 18 No. 1 hits and more than 200 million records sold, Carey spent many of her years in the spotlight suffering in silence.
She is now in therapy and taking medication for bipolar II disorder, which involves periods of depression as well as hypomania (less severe than the mania associated with bipolar I disorder, but can still cause irritability, sleeplessness and hyperactivity).
"I'm actually taking medication that seems to be pretty good. It's not making me feel too tired or sluggish or anything like that. Finding the proper balance is what is most important," Carey tells PEOPLE.