"Doing that film taught me that there is no room for fear," the actress tells PEOPLE of portraying cancer patient Hazel Lancaster
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Shailene Woodley worked with such accomplished pros as George Clooney (in The Descendants) and Kate Winslet (in Divergent), but it’s her The Fault in Our Stars costars who, she says, have taught her the most.

“I want to wake up every single day and be the best version of me. A lot of that has to do with Fault and meeting these 16- or 18-year-olds who had a week to live or passed away while we were filming,” Woodley tells PEOPLE about her role as cancer patient Hazel Grace Lancaster in the big-screen adaptation of John Green s best-selling novel. “Doing that film taught me that there is no room for fear. Zero.”

Working alongside real-life cancer patients on the tearjerker also came with a bit of guilt for the fearless actress.

“There is just no way to justify life,” she says. “Why am I here making this couple-million-dollar movie and eating a nice meal with [my costar] Laura Dern, and at the table right next to us is a 16-year-old boy with a tumor growing out of his head?”

But Woodley chooses to focus on the positive and has embraced the fact that life is fleeting.

“Are we going to spend life wallowing, or are we going to be stoked and laugh? We have no idea [when we will die], so it is just about living life to the fullest,” she says. “Laughing feels so good. I tell you, all my older friends laugh a lot and have no wrinkles. That is the secret to good skin, I swear. Everyone has this big thing about chemicals and facials, but it is just laughter.”

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