"It wasn't easy for my parents to talk about," The Wife actress Glenn Close tells PEOPLE's Editor-in-Chief Jess Cagle in the latest episode of The Jess Cagle Interview

Prior to landing roles in Fatal Attraction, Damages and The Shield, Glenn Close spent her childhood as a member of a cult-like religious group called the Moral Re-Armament.

Her father, a Harvard grad who worked as a doctor in Congo, joined up and moved Close and her family to Switzerland to be raised near the group’s headquarters in Caux. Close then attended boarding school, and it wasn’t until she was in the midst of studying acting at the College of William & Mary at age 22 that she ended up leaving the group founded in the 1930s by Rev. Frank Buchman, known for his belief that the world could avoid war if people experienced a moral and spiritual awakening.

The Moral Re-Armament largely died out when Buchman passed away in 1961, and his successor Peter Howard four years later.

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Close (middle) with her sisters Tina (left) and Jessie, was born in Greenwich, Conn.
| Credit: Courtesy Grand Central Publishing

“Each of us had to go through that process of forgiveness,” Close, who stars in The Wife, tells PEOPLE’s Editor-in-Chief Jess Cagle in the latest episode of The Jess Cagle Interview (streaming now on PeopleTV) of her family’s life after the Moral Re-Armament. “It wasn’t easy for my parents to talk about, certainly my father. But I guess I’ve made my career figuring out the why’s of behavior, and I did the same thing with my parents.”

Though the actress admits there was a time when she resented her father deeply.

“There came a point where I got very, very angry at my father and I wrote him this letter where I was absolutely honest with [him],” she recalls. “I said, ‘You don’t deserve to be called our father.’ I mean, it was so harsh. In fact, I read it to my mother and I read it to my siblings and I said, ‘I’m just going to send this to dad,’ because he was a narcissist and he was brilliant, brilliant, but he definitely had a dollop of narcissism.”

RELATED VIDEO: Inside the Church Cult That Eventually Drove Parents to Join a 12-Hour Beating of Their Sons

Close also believes her mother had a role in her strained relationship with her dad growing up. “I think in many ways my mom enabled him,” the six-time Oscar nominee continues. “She never developed her, where she was brilliant, to the point where she said to me, near the end of her life, ‘I feel like I haven’t achieved anything.’ ”

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Now, Close claims she understands how her parents became who they were at the time they entered the Moral Re-Armament.

TimesTalks with Glenn Close and Meg Wolitzer, New York, USA - 31 Jul 2018
Close in July.
| Credit: Griffin Lipson/BFA/REX/Shutterstock

“I’ve learned more and more about them and more about what their situation was and how vulnerable they were at certain times,” she says. “I think I really understand why they were so vulnerable to a group like that. Not knowing the devastation that it would cause their children.”

The Wife hits theaters Aug. 17.