Keke Palmer Shares How Being the Victim of Child-on-Child Molestation Impacted Her Life: 'I Felt Out of Control' (Exclusive)

The award-winning former child star reflects on a traumatic experience of being molested by a peer, and how it took her years to understand what had happened

MacMillan; Moviestore/Shutterstock Keke Palmer 'Master of Me' memoir; Keke Palmer 'Akeelah and t he Bee' in 2006

MacMillan; Moviestore/Shutterstock

Keke Palmer 'Master of Me' memoir; Keke Palmer 'Akeelah and t he Bee' in 2006

Keke Palmer experienced extreme highs and lows during her childhood.

The second-oldest of four children born to Sharon, a teacher, and Larry, a Catholic deacon, Palmer, 31, whose birth name is Lauren, grew up in a small town outside Chicago. “We were impoverished, but I felt so much love and a rich sense of community,” the actress tells PEOPLE in this week's cover story.

But at around age 5, she was sexually abused by a peer, a deeply traumatic event she mentions in her new book Master of Me: The Secret to Controlling Your Narrative, out Nov. 19. “People don’t really think about child-on-child molestation, but it’s something that exists,” she says. “I felt weird and violated, but I didn’t really know how to place it. I just knew I had all these weird feelings and thoughts, and I felt a little bit out of control and overwhelmed.”

Keke Palmer Instagram Keke Palmer with her parents Sharon and Larry Palmer and siblings, Loreal, Lawrence, and Lawrencia.

Keke Palmer Instagram

Keke Palmer with her parents Sharon and Larry Palmer and siblings, Loreal, Lawrence, and Lawrencia.

Palmer was drawn to performing, and her parents encouraged her to try acting. Her sister Loreal, 34, says her star power was evident even when she was little: “She’s always been the type of person who can walk into the room and talk to everyone. She was special. Her passion about what she does is always shining through.”

Related: Keke Palmer on ‘Inappropriate’ Relationship with Older Man While Filming Nickelodeon Show: ‘Nothing Makes It Right’ (Exclusive)

Phylicia J. L. Munn Keke Palmer PEOPLE Cover

Phylicia J. L. Munn

Keke Palmer PEOPLE Cover

Palmer landed her first small part in the 2004 film Barbershop 2 at age 10. It wasn’t until she was 12 that she realized how the early trauma she’d endured had shaped her.

“I was reading a book about sexual abuse, and it said all these things about anxiety and hyper-sexualization,” she explains. “All of this stuff that I attributed to me but really it was because of what I had experienced.”

When she finally processed the situation, "it wasn't about blaming that other child," she says, "we don't know sometimes what has happened to us, especially if it doesn't look the way that the world has told you it looks like."

Everett Keke Palmer in 'True Jackson VP'
Everett Keke Palmer in 'True Jackson VP'

A few years later she landed the starring role in True Jackson VP on Nickelodeon, and life changed for her entire tight-knit family, who moved to Los Angeles as her career took off.

“Fame shocked us,” she says. “It was a shock that I could make that much money, that I could go to Universal Studios and have a hundred people surrounding me at once."

Related: Keke Palmer Breaks Her Silence on ‘Unhealthy’ Relationship with Ex Darius Jackson: ‘Hardest Thing I Ever Had to Go Through’ (Exclusive)

She continues, "The weight of that was real bad, and we all felt it in so many different ways.” Becoming the family’s breadwinner as a tween “put a lot of pressure on my back,” she notes. “I had a great time doing True Jackson VP, but it was also a very stressful, difficult, depressive time.”

She also began dating an older man during that period. "I was 15, he was 20," Palmer says of the partner she doesn't name. “I was trying to balance between being really young, but also feeling quite mature. If I thought it was inappropriate, then I wouldn't have done it."

Phylicia J. L. Munn Keke Palmer

Phylicia J. L. Munn

Keke Palmer

"Obviously I shouldn’t have been 15 dating no 20-year-old," she adds, "but in my mind it was like ‘I got a full-time job. . . . Can’t nobody understand me but a grown man.’ But he knew there was a lot of stuff that there's no damn way for me to understand at damn 15."

She kept five-year relationship hidden from her parents and the world. “I wasn’t mentally able to process and understand things that would’ve made that relationship appropriate," she says.

For more on Keke Palmer's life and revealing new book, pick up this week's issue of PEOPLE, out Friday.

When she thinks about the struggles she's had with her mental health throughout her life, she says it isn't any one thing. "Yes, it's that experience [of molestation], but also the experience of being a child entertainer, that caused me a lot of anxiety, a lot of stress, a lot of depression."

In writing Master of Me, "my diving into my stuff is less about you saying, 'Me too,' and more about you being like, 'Let me dive into my stuff.' Because when you do dig, it's like, 'Okay, I can move forward with that awareness in a way that's going to allow me to not hold myself back."

Master of Me: The Secret to Controlling Your Narrative by Keke Palmer comes out Nov. 19 and is available for preorder now, wherever books are sold.