'Matilda' Child Star Mara Wilson Battled OCD and Depression – and More Revelations from Her Emotional Memoir

Mara Wilson will forever be beloved for her early but unforgettable turns in Mrs. Doubtfire and Matilda – but her life offscreen wasn’t always so charming.

In her witty first memoir, Where Am I Now?, excerpted exclusively by PEOPLE in the magazine’s new issue, Wilson writes that she retired from acting in Hollywood because she felt she didn’t measure up to the industry’s competitive beauty standards.

But that’s just one of many revelations the former child star, now 29, gets real about in her book and her interview with PEOPLE.

PEOPLE caught up with Wilson about more of the surprising stories she shares. Below are some of the biggest bombshells.

She was diagnosed with obsessive-compulsive disorder as a tween.
A self-described “perfectionist” and “worrier,” Wilson reveals she was diagnosed with OCD, depression and generalized anxiety disorder in the 7th grade.

Having sought treatment upon her diagnosis, the star is happy and healthy today.

“I’m good! I’ll always have those problems, at least, sort of on the periphery, but I know about them now, and I can recognize them in myself. I think that’s the most important thing, recognizing: This thing that I’m feeling right now isn’t right, isn’t true; it’s a part of my disorder, and it’s unhealthy,” Wilson says of managing her mental illness.

Wilson adds: “You just have to learn that and keep it in check. And you have to be honest about it and honest about the people who love and care for you [asking] ‘How are you right now? Is this making it worse?’ It’s something that I’m going to have to live with for the rest of my life, but I feel like it is livable.”

For more on Mara Wilson and an exclusive excerpt from her memoir, pick up the new issue of PEOPLE, on newsstands everywhere Friday.

She would often compare herself to her fellow child stars like Kristen Stewart and Scarlett Johansson.
In college, she writes in Where Am I Now?, “I’d pass newsstands on my way to class, clad in pajama pants, and see my former friends and peers, Lacey Chabert, Hilary Duff, Scarlett Johansson and Kristen Stewart, on magazine covers looking immaculate. It was fine, I told myself. That was never going to be me, anyway.”

And while she once saw these women as competition, she no longer compares herself to them.

“It’s funny, but I don’t [wonder where I’d be] if I’d stayed acting,” she says. “I think way more about what would have happened if I’d gotten out earlier than I do about what would have happened if I’d stayed in. I don’t know who I would be if I had stayed in. I would be totally different. I might be miserable. I think that I probably wouldn’t be super successful.”

Costars like Danny DeVito became longtime friends.
When Wilson was filming Matilda, her mother battled cancer, and director and costar Danny DeVito and his wife Rhea Perlman helped take care of Wilson while her mom was in the hospital.

“They’re great people; they were really there for me and my family,” says Wilson, whose mom died when she was 8, before the movie hit theaters. “. They had a movie theater, and we’d watch Oliver and Company and Twister and all these kids’ movies.”

She had a complicated relationship with her Matilda character.
“She is always going to be a part of me. For a while, I resented that – almost in the way a lot of people resent their parents when they’re growing up and they go through a rebellious phase and then, hopefully, if they have good parents, come to appreciate them. I think that’s a little bit how I felt with Matilda,” Wilson says. “This was someone who had given me a lot of opportunities, but then I came to resent that influence in my life. But I’ve eventually come to appreciate it. Young women didn’t see many characters like that. So she was a revelation, and she meant a lot to them.”

She was a show-choir nerd and went to the high school Glee was reportedly based on.
Wilson attended John Burroughs High School in Burbank, which is known for its competitive show-choir scene.

“It was years before Glee. We had a whole subculture inside of it,” Wilson says. “That’s like a little teen drama. Altos thought the sopranos were jerks, and there was a lot of tension there.”

She (briefly!) tried online dating.
Wilson graduated from New York University, now lives in Queens, New York, and had an OkCupid dating profile “for a second” – but says, “I think I need to meet people in real life and get to know them.”

“I haven’t been on in years. I never met anybody lasting on there,” she says. “There are a lot of people there who know me for what I did as a child, and you can’t date your fans because it’s not fair to them, and it’s not really fair to you either. Of course, not everybody knows who I am, and that’s why I’ve been able to date anybody at all, I guess!”