>>>Paris Hilton recounts her stories of abuse while at Provo Utah Canyon Youth Behavioral Health Facility

In a revealing new documentary, Paris Hilton opens up about a trauma she’s never publicly discussed.

“I feel like the whole world thinks they know me because I’ve been playing this character for so long,” Hilton says in the film, “This Is Paris,” which then cuts to a clip of her 2000s reality show “The Simple Life.”

“That’s not me,” Hilton, now 39, continues. “No one really knows who I am. Something happened in my childhood that I’ve never talked about with anyone. I still have nightmares about it. I wish I could bring a camera into my dreams and show you what it’s like. It’s terrifying. And I relive that every night.”

In 1996, Hilton’s family moved from Los Angeles to New York. Hilton says she struggled with bullying at her new school and her parents’ expectations for her and younger sister Nicky Hilton to attend etiquette classes and follow their strict rules. She rebelled by sneaking out to nightclubs, where she felt “accepted.”

It was then, she says, that parents Kathy and Rick Hilton sent her to a series of “emotional growth schools.” After running away from the first two, Hilton was sent to Utah’s Provo Canyon School, which she describes as “the worst of the worst.”

“You’re sitting on a chair staring at a wall all day long, getting yelled at or hit,” she says in the film. “I felt like a lot of the people who worked there got off on torturing children and seeing them naked. They would prescribe everyone all these pills. I didn’t know what they were giving me. I would just feel so tired and numb. Some people in that place were just gone, like the lights are on, no one’s home. A lot of people were on suicide watch, and I was so scared that was going to happen to me.”

“Eventually I found out a way to not take the pills,” she adds. “But everyone would tell on everyone, and they found a Kleenex with all of the pills in it. I got into so much trouble for that. Solitary confinement, like something out of ‘One Flew Over the Cuckoo’s Nest.’ They’d make people take their clothes off and go in there for 20 hours. It felt like I was going crazy. Someone was in the other room that was in a straitjacket screaming. I was just freezing, I was starving. I was alone, and I was scared.”

Hilton says her parents were still in New York and she didn’t notify them of what was happening for fear of being punished. She alleges that the school’s staff told her, “We’re just going to tell your parents you’re a liar and they’re not going to believe you.”

A representative for Provo Canyon responded to the allegations in a statement to TODAY: “Originally opened in 1971, Provo Canyon School was sold by its previous ownership in August 2000. We therefore cannot comment on the operations or patient experience prior to this time.”

The statement added, in part: “Provo Canyon School today is an intensive, psychiatric residential treatment center for youth between the ages of 8 and 18 that have special, and often complex, mental health and emotional needs. We offer innovative, evidence-based therapeutic interventions, academic instruction and life-skills training tailored to the needs of each of our students.”

In 2000, Universal Health Services acquired Provo Canyon from Charter Behavioral Health Systems, which filed for bankruptcy. A spokesperson for UHS declined to comment on Charter’s operations for this story. TODAY also reached out to Magellan Health, which owned a 50 percent stake in Charter until August 1999, but has not received a response.

“I was at Provo for 11 months and the only thing that saved my sanity was thinking about what I wanted to do and who I wanted to become when I got out of there,” Hilton says. “I was going to do everything in my power to be so successful that my parents could never control me again. When I turned 18 and got out of Provo, it was one of the happiest moments of my life.”

Later in the film, she tells Kathy Hilton of the abuse and her mother responds, “Had I known this, know that Dad and I would’ve been there in one second.”

According to Hilton, the effects of her treatment at the school have included insomnia, recurring nightmares and difficulty forming healthy relationships.

“After being at Provo, you don’t even know what love is or how to have a relationship,” she says. “I’ve been in a lot of relationships where people get so controlling and so angry that they become physical.”

“I’ve been strangled, phones thrown at me, computers,” she adds. “And I accepted it because I almost thought it was normal. It was like, ‘He loves me so much that he’s going this crazy.’ I just wanted love so bad that I was willing to accept being hit or yelled at or screamed or strangled or a lot of things.”

Hilton says that the sex tape ex-boyfriend Rick Salomon released in 2004 wouldn’t exist if not for the abuse she suffered years before as a teen: “I was just so lost and desperate for love that I found the worst possible person.”

While Hilton says she was hesitant to speak out about her experience, worrying that it would affect her brand, she hopes that coming forward will prevent other kids from experiencing abuse and help heal her own trauma.

The film shows her meeting with former Provo Canyon classmates, who discuss the school’s impact on their lives two decades later and shoot a social media campaign for Breaking Code Silence, a movement to raise awareness for problems in the “troubled teen industry.”

“I feel like this is the best point I’ve ever been in in my life,” Hilton says following the reunion. “We were really talking about our lives and things that affected us and making a change and a difference. It just made me feel like I wasn’t alone anymore.”

“This Is Paris” will premiere on Hilton’s YouTube channel Sept. 14.