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Cara Delevingne has already conquered the modeling, acting and singing worlds, and now, she's trying her hand at YA fiction. In her cover interview in this week's issue of Net-a-Porter's The Edit magazine, she explains how her own struggles with depression and suicidal feelings as a young adult helped her capture the angst of her teenage protagonists in Mirror, Mirror, which hits stores next week.

Delevingne said her mental health began to suffer as a result of her struggles in the classroom. "If I fail at something, it's the worst thing in the world because I never forgive myself," she said. "I didn't feel like I was ever good enough. The fact I couldn't do as well as other people made me hate myself. And you're made to feel that once you get a mark, like a C, that's your mark in life; that's you as a human being. That really sat with me for a long time."

"I always felt pretty weird and different as a kid, and that feeling was something I didn't understand, or know how to express," she continued. "I wish I could have given myself a hug. I wish I'd known that I was still in there somewhere, that I wasn't my own worst enemy, that I wasn't trapped. That if you can hold on for dear life — because being a teenager can feel like you're on a rollercoaster to hell, that's what it honestly felt like to me — you can get through it. Time moves on, feelings pass, it does get better."

Delevingne said she felt "something dark" within herself as a teenager, despite her privileged upbringing, and that being a late bloomer only made things worse. "I felt alienated and alone, because I was like, what's wrong with me? I always wanted people to love me, so I never got angry with them; I turned my anger onto myself," she said, and shared that she had to take a break from school when she was 15 to receive treatment for a breakdown. "I hated myself for being depressed, I hated feeling depressed, I hated feeling," she said. "I was very good at disassociating from emotion completely. And all the time I was second-guessing myself, saying something and then hating myself for saying it. I didn't understand what was happening apart from the fact that I didn't want to be alive anymore."

Since then, the 25-year-old has made her way to a healthier place, one where she no longer depends on the people around her to feel happy and fulfilled. "I know it sounds really stupid, but I relied too much on love, too much on other people to make me happy, and I needed to learn to be happy by myself," she said. "So now I can be by myself, I can be happy. It took me a long time."

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Delevingne isn't alone in opening up about her mental health. Stars like Emma Stone, Lili Reinhart, and Zayn Malik have all also taken advantage of their platforms of late to help destigmatize and start open conversations about depression and anxiety.

Related: Cara Delevingne Sets the Record Straight on Her Sexual Fluidity

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