WWE Hall of Fame Nikki Bella, is opening up about a very painful time in her life.

In her upcoming tell-all memoir, "Incomparable," co-written with her twin sister Brie Bella, Nikki reveals that she was sexually assaulted twice as a young teenager and speaks about how the incident affected her self confidence and mental health growing up.

When the "Total Bellas" star was 15 years old, she writes that she was raped by someone she "thought was a friend" and then at 16 years old she was drugged and raped by a college-aged man.

"There is the horrible offense in the moment, and then the shame and blame that follow and feel almost worse than the original pain," the 36-year-old said, according to People magazine.

"When something like this happens to you, you understand the blame-the-victim mentality, how easy it is to feel shame rather than anger, how easy it is to feel like you could have stopped it yourself," she added.

Nikki, who is pregnant with her first child, said she spent years blaming herself and feeling ashamed so she kept the incidents a secret.

"And keeping that a secret and blaming myself, I started to lose my confidence," she said.

"I started to disrespect myself. And then the relationships I got into at a young age, I let other people disrespect me and felt like, that's OK, this is what I deserved."

The former WWE star said she dealt with the trauma by going to therapy "on and off" for years but wishes she would have "let go" of the emotions earlier in life because "so much would have changed."

Now, Nikki is hoping her story can help others struggling in a similar situation and inspire hope.

Nikki Bella reveals she was raped twice as a teen: 'I started to lose my confidence'

"When the #MeToo movement happened, I was just like, 'Oh my gosh,'" she confessed.

"I feel like, if I'm having these younger women look up to me, maybe I can help them and have them not hold onto this as long as I did. It wasn't until I was 28 and in a relationship where someone started to teach me how to respect myself."

"That's how long I held on to things and felt I had no boundaries. And I'd always look at Brie like, 'Oh, she has boundaries, she treats herself with such respect. How do I not have this?' And I knew why. But I held onto it for so long. When I look back at just decisions I made based off of it, I wish I could have heard my words now as a 36-year-old woman then, and be like, 'You're going to be OK,'" she added.

She however disclosed that she regained confidence in herself when she started dating John Cena.

Bella said her relationship with John Cena helped her start to learn to "respect myself."

The couple dated from 2012 to 2018, when they broke off their engagement.

Bella is now engaged to Dancing with the Stars dancer Artem Chigvintsev. They are expecting their first child this year.