Nicole Kidman was basically the green light for HBO’s Big Little Lies. After meeting the novel’s author Liane Morarty, they both made a deal that if the Academy Award-winning actress would play “Celeste Wright” (the lawyer turned battered housewife), Liane would give the rights to Nicole and Reese Witherspoon to produce the project.

Now, the show is a hit. But Nicole is left to the aftermath of her character’s hell. After all, playing a housewife who is constantly abused by her husband can leave an invisible mark — on and off screen.

“One of the most important scenes in the series is when I go and find Max and hold him and whisper to him, and say, ‘People do bad things but that doesn’t mean that’s you. We can change this. I’m here,’” Nicole said to Entertainment Weekly. “She deals with her child with love instead of punishment. That to me is Celeste’s shining moment. That’s her heart and I love that’s the choice there. She knows she’s responsible. Though they weren’t seeing [the abuse], they were absorbing it. She feels that and she knows that’s the parenting that’s been going on and it’s affected one of their children. And that’s devastating to her. It’s also why she can finally leave. This is what I find deeply sad, I’ll put up with things, I’ll absorb thing, as long as my children are protected. As soon as my children are exposed, and she sees it, then she can act, then she can move, then she’s propelled. And that just cuts me to my core.”

On her feelings about playing Celeste: “There were days and days of doing a lot of aggressive, really violent scenes. And I would go home and have a shower or have a bath and I would weep at home. And it would be like, ‘Oh my gosh, what is happening to me?’ And then one day, I just got a rock and threw it through a glass door! Yes. Where I was staying. And I threw a rock. I must have had a lot of pent-up [stress], because I was trying to hold it all in. I’ve never done that in my life. And then I just started crying and crying and crying. It just penetrated my psyche in a way a film never had.”

She also ended up going home with bruises at one point: “I don’t know if he had any bruises. He probably did. (Laughs) But I did,” she said. “I was covered in them. My body was in pain. That’s how I describe it. I don’t usually take Advil and I would take Advil. I was living through it. I felt the necessity to do that for the truth of this story, which I feel is a very important story to tell. It’s insidious how these things happen. The things that start to become normal when they aren’t normal and the things we allow. And how a relationship can morph into where both people in it are not bad people. And he is very sick. He’s not well.”

Read the full interview at Entertainment Weekly, and don’t forget to watch Big Little Lies on HBO!