Between breaking a Guinness World Record for her towering vocal power and nabbing a No. 3 spot among the nation’s best-selling female artists, fans may assume they know everything there is to know about the Songbird Supreme, Mariah Carey.

Unfortunately, that’s not the case, however, after she revealed in an exclusive cover story with PEOPLE that she has been battling bipolar II disorder for quite a while.

According to the site, Mimi is currently in therapy and also takes medication for the disorder. Bipolar II symptoms include depressive and hypomanic episodes that can sometimes last four days or more. Though less severe than the hypomania suffered from bipolar I disorder, type two bipolar brings about insomnia, increased distractibility and frequent irritability.

It’s no wonder, then, that she believed she only suffered a severe sleep disorder prior to her diagnosis, Mariah said.  

“But it wasn’t normal insomnia and I wasn’t lying awake counting sheep,” she said in the interview. “I was working and working and working … I was irritable and in constant fear of letting people down. It turns out that I was experiencing a form of mania. Eventually I would just hit a wall.”

She described her depressive episodes as feeling low on energy, and constant feelings of loneliness, sadness and even guilt. Thankfully, Mariah said elsewhere in the story, the medication she’s currently taking has minimal side effects that don’t increase fatigue or sluggishness. The Glitter actress is “in a really good place right now,” which prompted her to disclose her battle with the mental health disorder. Not to mention, she said, the intimidation of living with the disorder so secretly placed in her in a perpetual state of paranoia.

“Until recently I lived in denial and isolation and in constant fear someone would expose me,” she revealed. “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.”

Mariah hopes that opening up about her battle will prompt others to detach stigmas from the disorder and others who suffer from bipolar II to liberate themselves as well.

“It does not have to define you and I refuse to allow it to define me or control me,” she concluded.

BET sends love and light to Mariah amid her new revelation and other individuals battling a mental health disorder. We encourage those seeking more information or support to visit the Depression and Bipolar Support Alliance at dbsalliance.org.