Princess Diana struggled with mental issues alone, but she became strong enough to help herself in the end.

Through the documentary entitled "Diana: In Her Own Words," royal watchers discovered what happened during the interview of Princess Diana with her friend James Colthurst at London's Kensington Palace in 1991.

Princess Diana's brutally honest stories focused not only on how Prince Charles became unfaithful to her but also how he spoke impertinent comments that caused her to have an eating disorder.

According to the late royal princess, her bulimia battle started even before she got engaged with Prince Charles. It began when the heir to the throne held her waistline and said, "Oh, a bit chubby here, aren't we?" -- prompting something unpleasant inside her.

Moreover, a few months after their 1981 Wedding of the Century, Diana's suicidal thoughts got even worse to the point that the royal family sought for the experts to "fix her."

"I was about to cut my wrists. I came [back to London] to seek treatment. I was in such a bad way. Couldn't sleep, didn't eat, the whole world was collapsing around me," Princess Diana revealed.

Diana added that analysts and psychiatrists gave her high doses of valium, a medication to calm her down, in pursuit of "sorting her out."

But years after she was diagnosed with the said disorder, Diana pushed herself to overcome it.

Princess Diana Did This to Feel Better

Jenni Rivett, a well-known celebrity trainer, became Princess Diana's key to finally free herself from her inner demons.

According to Rivett, the Princess of Wales engaged herself in physical exercise thrice a day as part of her healing process. Aside from working out, Princess Diana also garnered a sense of discipline that made it easier for her to stay dedicated.

"Actually she had an incredible sense of humor. The way that was brought up was with a joke. She was just trying to make light of it," Rivett told Express.

Princess Diana saw her disorder as her way to harm herself quietly after she abruptly had a relationship with Prince Charles.

The "Diana Effect"

Since the sunny-looking princess' disorder became known worldwide after she spoke about it publicly, a lot of women in Great Britain sought treatments for the same mental health issue.

Due to this phenomenon, the media called it the "Diana effect." 

Moreover, mental health professionals credited this occurrence to spread awareness to the public. According to those women who saw Princess Diana's suffering, they could also be bulimic if the princess agonized from it. And if she could overcome her eating disorder, they could, too.

Researchers have found that knowing someone else with a mental illness can encourage others to get help.

As stated in the 2005 book British Journal of Psychiatry, the authors focused on how Princess Diana's death helped people to overcome their mental health disorders.

"It is notable that the Princess's death in 1997 coincided with the beginning of the decline in bulimia incidence," researchers stated. "Identification with a public figure's struggle with bulimia might have temporarily decreased the shame associated with the illness, and encouraged women to seek help for the first time."

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