One of the most talked-about parts of the new release is his words about his past relationships - particularly referencing how difficult it was for his ex girlfriends, dating under public scrutiny. Not to mention, how upsetting he found watching their lives get turned upside down.
Chelsy Davy plays a prominent role in Spare, dating Harry on and off for seven years, during which time she was followed by photographers and hounded by paparazzi, something that ultimately led to their break up - as Harry recalls in the memoir.
Cressida Bonas and Caroline Flack are two other former girlfriends whose lives were similarly turned upside down when their relationships with Prince Harry were made public.
This week, it was a lesser known past girlfriend of Prince Harry's that made news, as he recalled his secret relationship with Florence Brudnell-Bruce back in 2011, and how once again it was broken up by the press scrutiny.
Describing her as "brilliant, beautiful [and] cool", Prince Harry recalled how he and Florence [known as Flea] were introduced by mutual friends who told him "she won't be single long."
"Over that first cup of Earl Grey, I was asking myself: 'Could she be my person?'", Harry recalled of going back to her Notting Hill flat after being introduced at a bar. "The connection was that strong. But I was also that mad. And I could see she knew it, read it all over my non-poker face. I hoped she found it charming. Apparently she did.
"The weeks that followed were idyllic," he continued. "We saw each other often, laughed a lot and no one knew. Hope got the better of me. Then the press found out and down came the curtain on our idyll.
"Flea phoned me in tears. There were eight paps outside her flat. They'd chased her halfway across London," Harry recalled. "She'd just seen herself described by one paper as 'an underwear model'. Based on a photoshoot done years and years before! Her life boiled down to one photo, she said. It was so reductive, so degrading. 'Yes', I said quietly. 'I know what that feels like'.
"They were digging, digging, ringing up everyone she'd ever known. They were already after her family. They were giving her the full Caroline Flack treatment, while still giving it to Caroline as well.
"Flea just kept saying: I can't do this," he recalled. "She said she was under twenty-four-hour surveillance. Like some kind of criminal. I could hear sirens in the background. She was upset, crying and I felt like crying but of course I didn't.
"She said one last time: 'I can't do this any more Harry'," he continued. "I pressed my face against the window's cold polished glass and asked Flea to see me one last time, at least talk it over. 'No'. She was firm."
Later in the passage, Harry recalled: "[A] friend told me he'd heard that it was Flea's mother who told her to end things, who warned her that the press would destroy her life. 'They'll hound you to the gates of Hell', her mother said. 'Yeah', I told the friend. 'Mums do know best'."
Spare is available to buy now.
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Jenny Proudfoot is an award-winning journalist, specialising in lifestyle, culture, entertainment, international development and politics. She has worked at Marie Claire UK for seven years, rising from intern to Features Editor and is now the most published Marie Claire writer of all time. She was made a 30 under 30 award-winner last year and named a rising star in journalism by the Professional Publishers Association.
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