Before she was even 20 years old, Keira Knightley had the career most actors only dream of having. But sometimes success isn't all it's cracked up to be.

In a new interview with Balance, Knightley opens up about personal struggles in her early years, despite a series of box-office hits. From Star Wars: Episode 1 at just 14 years old and Bend It Like Beckham at 16, to Pirates of the Caribbean and Love Actually at 17, you'd think Knightley would have been on top of the world.

Knightley was growing up and figuring out who she was, all very much in the public eye. "I lost confidence in myself," the British actress says. "People were being very vocal with their views on me as a young woman and as an actress."

"Looking back, that whole period between 19 and 23 is a big blur," the actress tells Balance. "I don’t remember it in a linear way because I think my coping mechanisms were kicking in and shutting a lot of it out."

Shutting it all out could only last so long. “My world crashed when I was 22,” the actress says, referring to a breakdown. “I felt as if I was broken into tiny pieces; as if my brain was literally shattered.”

Knightley initially coped by taking a year off from working, traveling extensively. At one point she wasn't even sure if she'd return to acting. "I’ve always loved acting; it’s just everything else that comes with it that I was struggling with," she tells Balance. The actress eventually underwent extensive therapy, including hypnotherapy, which she says helped.

Now 33, Knightley is married and the mother of three-year-old daughter Edie, and facing a whole new world of challenges. "I don’t think we give women enough credit for the physical and emotional marathon they go through when becoming a mother,” she says.

“I come from a place of amazing privilege. I have an incredible support system; I’ve been unbelievably lucky in my career; I can afford good childcare, and yet I still find it really f-cking difficult," Knightley says candidly about motherhood. "It’s OK to say that. It doesn’t mean I don’t love my kid, it’s just me admitting that the sleep deprivation, the hormonal changes, the shift in relationship with my partner, are all things that make me feel as if I’m failing on a daily basis. I have to remind myself that I haven’t failed, I’m just doing what I can do, but it’s not easy.”

We love to hear celebrities open up like this, speaking honestly about difficulties outside the spotlight. When public figures speak up about these ups and downs, it not only makes them seem more human, it normalizes things like anxiety, depression, and other real-life struggles.

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