"I was building my life around this image of perfection, and it was really oppressive,” says the musician in this week's issue, ahead of her new book release

Alicia Keys Reveals Her Lifelong Struggle to Find Herself in New Book: 'I've Been Putting on a Mask'

Alicia Keys isn’t who you think she is. She isn’t even who she once thought she was.

In this week’s issue the superstar singer and 15-time Grammy winner opens up to PEOPLE about her emotional new autobiographical book More Myself, sharing an exclusive excerpt that reveals her lifelong battle to find and live her truth.

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For years, “I was building my life around this image of perfection, and it was really oppressive,” says Keys, 39, who recalls once feeling “emptiness” and nearly crumbling under the pressure of her skyrocketing career back in 2006. “I was clearly a woman who wanted to talk about truth and empowerment and strength, but when I really looked at myself, I realized that my whole life I’ve kind of been putting on a mask.”

For Keys, born Alicia Augello-Cook, that mask came in many forms. Growing up in Manhattan’s Hell’s Kitchen neighborhood in the ’80s, she adopted a tough tomboy persona to survive and hide the pain of not seeing her father Craig Cook, who rarely visited her after he and her mother Teresa Augello conceived Alicia during a brief relationship.

For more on Keys’s journey to find love and love herself, pick up this week’s issue of PEOPLE on newsstands Friday or subscribe here.

Image zoom This week’s PEOPLE cover

“For me, a seed of worthlessness was planted in childhood,” writes Keys. “As well-intentioned as Craig was, and as much as he was dealing with in his own life, his absence impacted me in ways I’m still uncovering. It left a hole in me.”

It was a hole, her mother worked tirelessly to fill, reassuring her of her value. “Race was never a part of what made me feel guarded,” writes Keys, whose mother is Scottish-Italian and whose father is black.

Image zoom Alicia Keys and Teresa Augello

“You’re the best of both worlds,” my mother would often remind me. And she was right. Yet since my mother understood that America would compel me to choose, she raised me with an awareness that’s still intact: I am a black girl.”

While she excelled academically, skipping two grades and graduating high school at 16, Keys admits to doing her share of misbehaving.

“At any one of the shops on the street around the corner from our apartment a kid could get anything: a fake ID (like the one I used to sneak into a club called Tunnel), a fistful of blunts (I smoked my share), a pack of condoms (which led to the used one that somehow got lost under the couch on the afternoon I lost my virginity). My mother had to be strict as a matter of my survival.”

Image zoom Alicia Keys LEE CELANO/AFP via Getty

But that all changed when she made it big in 2001, after her hit debut album Songs in A Minor launched her to stardom. It was around then she found herself painted into the image of music’s soulful princess, and the pressures of the industry became daunting.

The star recalls a sense of helplessness during one of her first photo shoots:

“‘Open up your shirt a little,’ [the photographer] directs while firing off a flurry of snaps. My spirit is screaming that something is wrong, that this feels slimy. ‘Pull the top of your jeans down a bit in the front,’ he urges. I swallow my misgivings, tuck my thumb between the denim and my skin, and obey. On the day of the cover’s debut, I pass a newsstand where the magazine is on display. I almost throw up.'”

Image zoom Alicia Keys Taylor Jewell/Invision/AP/Shutterstock

Years later, in 2006, Keys says she felt a deep sense of “emptiness” and was close to an emotional breakdown due to the career and personal stress she was under. It led her to take a sabbatical and she sought refuge on a solo trip to Egypt.

Keys found love and support in husband, Swizz Beatz, 41, whom she married in 2010, and their sons Egypt, 9, and Genesis, 5. But struggles with self-doubt and insecurities continued to pervade her life for years.

Image zoom Swizz Beatz and Alicia Keys with their sons Egypt and Genesis Anthony J. Causi/Splash News

She writes, “There had been one afternoon, as I was preparing to pick up Egypt from school, I threw on some sweatpants and a baseball cap as an internal deliberation arose: ‘What if someone sees me like this and asks to take a photo? And what if that picture gets posted?’ The dialogue wasn’t new. On this day, I caught myself in the middle of the neurosis, and it socked me right in the gut.”

In 2016, the star published her now famous open-letter about loving herself without makeup and kicked off the viral #NoMakeup movement. It’s just one of the steps Keys has taken to move closer to who she wants to be, and who she feels she really is at her core.

Image zoom Alicia Keys Jeff Kravitz/FilmMagic

Looking back, “I wasn’t fake, but I was trying to live up to all these fake ideals,” Keys says now. “It was like a habit. I had to start to break it.” These days, she’s speaking her mind a lot more, and feeling as confident on this inside as she portrayed to others all these years. “I feel more like an open book. That’s a beautiful thing.”