Having dealt with anxiety ever since she was young, Roth found it therapeutic to create a 16-year-old heroine, Beatrice, who faces fears head-on.
"She's someone I admire in certain ways because of her willingness to take bold action when it feels like the right decision," Roth, 25, tells PEOPLE.
But Roth's own anxieties have nothing to do with climbing Ferris wheels or zip-lining across the big screen, as it does with her heroine, Tris.
"People often conflate fear and anxiety, but they're not the same thing," says Roth. "All human beings have fears because fear is healthy. Anxiety is unhealthy."
Roth was a nerdy perfectionist growing up, always putting a lot of pressure on herself. And in recent days, her anxiety has spiked thanks to new triggers, such as press events, photos and speaking in front of crowds.
"Anxiety keeps you in a kind of self-made prison," she says. "It keeps you from doing things you otherwise might have because you're too terrified."
Roth is back in therapy for her disorder and feels fortunate to have access to the help that she needs. "I'm working very hard to get it back down again," she says.
As an adult, she has learned not to feel ashamed of her anxiety.
"I do still think there's a stigma associated with it – as if it means a person is inherently weaker than other people if they struggle with mental illness," Roth says. "Your brain can have a condition, just like your stomach or your pancreas. Doing what's necessary to treat that condition is a good thing."
The new screen adaptation of Divergent opens Friday.
Reporting by KENNETH MILLER
For more on Veronica Roth, pick up the latest issue of PEOPLE, on newsstands Friday
And pick up the Divergent special issue from PEOPLE – on sale now!