Just over a year after Philip Seymour Hoffman died of a drug overdose, Mimi O'Donnell, his life partner and mother of his three children, recalls the grief that brought her back to work in theater where they first met.

O'Donnell first met Hoffman in 1999 and tells The New York Times that during her mourning of the "Capote" actor she took family trips to the beach, read books about grief from authors such as Joan Didion and Joyce Carol Oates and eventually returned to work.

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"I was pretty stubborn in my falling apart," she recalled. "And my kids saw all of it, because they should. What, am I going to hide it from them? I don't want them to hide it from me."

O'Donnell - who once served as a costume designer for "Saturday Night Live" - is now serving as the artistic director of the Labyrinth Theater Company, like Hoffman once was, and is directing a new play titled "Nice Girl."

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She admits returning to the theater world has acted as a coping mechanism. O'Donnell attended her first Broadway show since the death of Hoffman this summer when she saw the Oscar winner's longtime friend Cate Blanchett star in "The Maids."

"I go in feeling whatever I'm feeling about grief, and all of a sudden there's something onstage that's happening -- it cracks something open," she said. "When they really, truly open up in front of you emotionally, there's something about it that I find humbling as a human being.

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Now, over a year after Hoffman's death, O'Donnell is slowly healing. "I would say that, after a year has passed, I'm able to function, if that's the right word, or be in the world a little bit differently," she said.

Hoffman passed away on February 2, 2014. He was 46.