Nikki and Brie Bella Hope to Inspire Others by Sharing Painful Details of Their Childhood

Nikki and Brie Bella are sharing details of their painful past.

In their new co-memoir, Incomparable, the Total Bellas stars, both 36, give readers a glimpse at what life was like for them growing up. From loss and abuse to addiction struggles and relationship woes, the WWE Hall of Fame inductees share how they overcame adversity — and eventually found purpose through it all.

Speaking with PEOPLE in this week's issue, the sisters open up about their decision to share the intimate details of their life journey thus far.

"We have always been open books," Nikki tells PEOPLE. "That was one thing that we always wanted to commit to our families. That was, we have to be real and open, whether people love us or hate us for who we are, we owe them that. Brie and I have always been very intimate with our Bella Army and very connected, and the more we did reality [TV], the more we got to connect with people who were relating to us. Sometimes I would hear their stories and they would inspire me and motivate me."

• For more from Nikki and Brie Bella, pick up this week's issue of PEOPLE, on newsstands Friday

When the opportunity to write a co-memoir presented itself, the Bellas were more than ready.

"Let's tell [our story] and show everyone else that you don't have to stay a victim your whole life," Nikki says. "You can overcome this. You can be strong, you can be empowering, you can be free of your past. And that's what made us want to do it, was honestly to help others."

"Nicole and I were so lucky that we're always categorized as being strong women," adds Brie. "And a lot of that comes from WWE, being professional wrestlers, being women in a male dominated industry. The last seven years you did get to see our lives on television. But my sister and I thought it was important to write a memoir that let people know that it wasn't just wrestling that defined us as strong women. It was our childhood."

Growing up in an unstable home environment (their father battled substance abuse for years), the twins were greatly affected. But even more trauma followed.

In the book, Nikki opens up about being raped twice: once at age 15 by a fellow high school student she “thought was a friend,” and again when she was 16 after being drugged by a college-aged man.

“Because of how my father was when we were young and what happened to me, it made me hate men,” says Nikki. “I wanted to keep it a secret. I felt so ashamed and blamed myself.”

With time and therapy, Nikki says she eventually learned to let go of the past and hopes her story can help those who have been abused. “If I’m having these younger women look up to me, maybe I can help them and have them not hold on to this as long as I did," she says.

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Brie also faced trauma as a teen — specifically when her boyfriend, Bear, was killed in a car accident.

“Death is such a profound thing that can happen to people,” she says. “People come into your lives and they change you, and he did that. He changed me, spiritually.”

Following years of ups and downs, Nikki and Brie eventually found their footing in the WWE ring, where they broke gender barriers in professional wrestling.

Now, Nikki, who is pregnant and engaged to her former Dancing with the Stars partner Artem Chigvintsev, and Brie, who is also pregnant and just celebrated six years of marriage with husband Daniel Bryan (the couple have a 2-year-old daughter, Birdie), are looking forward to the next chapter of their lives — and hoping their stories can help people.

Says Nikki: “I hope whoever reads the book will throw on whatever imaginary cape they dream of and say, ‘I’m the hero of my own story and will conquer whatever I want to do!’ ”