Reese Witherspoon is opening up like never before about a difficult time in her life.

During an interview with her Wrinkle in Time co-star, Oprah Winfrey, as part of Super Soul Sunday, the 41-year-old actress shares that the "most difficult decision" she ever had to make to fulfill her destiny was "leaving an abusive relationship."

When Winfrey asks Witherspoon -- who was also joined by Mindy Kaling -- to elaborate, the Oscar winner says she faced "psychological, verbal" abuse on several occasions from a person in her past.

As for what led her to leave the relationship, Witherspoon recalls, "A line got drawn in the sand and it got crossed, and my brain just switched and I knew it was going to be very difficult but I just couldn't go any further."

She adds, "But it was profound and I was young."

Witherspoon believes that it was this moment that altered the trajectory of her life. "I could never be the person I am today," she explains. "It changed who I was on a cellular level, the fact that I stood up for myself. None of those leaving those situations ...it's wrought with self-doubt, particularly if someone damages your self-esteem."

She continues, "People say to me that knew me then, 'You're a completely different person.' I didn't have self-esteem. I'm a different person now and it's part of why I can stand up and say, 'yes, I'm ambitious' -- because someone tried to take that from me before."

Witherspoon notes that it was her own experiences that led her to produce and star in Big Little Lies, which addresses the complexities of domestic abuse. "There wasn't a woman there that hadn't been affected by abuse," she says of working on the HBO show.

Winfrey also recalls her experience with verbal abuse in her '20s. "I lived in that superior, better-than-though space where, 'As long as he doesn't hit me, he can say anything, he can do anything, but as long as he doesn't hit me,'" she says, recounting that it wasn't until her hand was slammed into a door that she realized she "had become that woman who would allow myself to be psychologically, verbally assaulted."

Witherspoon, Winfrey and Kaling also cover the March issue of O magazine, on newsstands Feb. 13, and the Queen of Talk speaks on the anti-harassment movement Me Too. "I’ve seen this happen over and over and over again," Winfrey begins. "The moment you release the thing that has held you in chains or that has made you feel shamed or disappointed in yourself, there’s always, always, always, another person saying, ‘Me, too.’”

Optimistic about the future, Witherspoon adds, "Social media has opened up a conversation that was not possible even 10 years ago. Women are talking about things they’ve never spoken about, and they’re actually being heard."

Back in October at Elle's 24th Annual Women in Hollywood Celebration, Witherspoon delivered an emotional speech where she revealed that she had endured sexual harassment and assault as a young actress in Hollywood.

 "[I feel] true disgust at the director who assaulted me when I was 16 years old and anger at the agents and the producers who made me feel that silence was a condition of my employment," she said. "I’ve had multiple experiences of harassment and sexual assault and I don’t speak about them very often."

Check out more of her empowering speech:

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