Ellen DeGeneres just shared a heartbreaking detail about her past. She also warned girls against sexual abuse.

In the Netflix series “My Next Guest Needs No Introduction,” the TV host told interviewer David Letterman that her stepfather molested her when she was just a teenager. DeGeneres said that the sexual abuse first took place while her mom was struggling with breast cancer.

When the award-winning host was just 15 or 16 years old, her stepfather convinced her that he needed to touch her breasts to check if her mom really had a lump in hers. What initially happened once repeated many times over.

DeGeneres said that she didn’t want to tell her mom what happened because she was protecting her. But one thing that the host learned is that she should’ve protected herself instead.

Several years passed and DeGeneres finally gathered up the courage to tell her mom what happened, but she didn’t believe her. The host’s mom stayed with her stepfather for 18 more years, and they only split after DeGeneres’ mom noticed that her partner kept changing his story about abusing her daughter.

“I have always taken care of her my whole life,” DeGeneres said. “So I just kept taking care of her. I didn’t really let it get to me. Until recently, I kind of went, ‘I wish I would have been better-taken care of. I wish she would have believed me.’ And she’s apologetic, but, you know…” she added.

Ellen DeGeneres told Letterman that she wanted to talk about her sexual abuse to encourage girls and women to speak up. She also said that most women don’t feel that they’re worthy to have a voice but they are.

“That’s the only reason I think it’s important to talk about because there are so many young girls, and it doesn’t matter how old you are. And when I see people speaking out, especially now, it angers me when victims aren’t believed because we don’t just make stuff up,” she said.

“My Next Guest Needs No Introduction” will premiere on Netflix on May 31.

Ellen DeGeneres Ellen DeGeneres at the People's Choice Awards in 2015. Getty