Princess Margaret's Son's Ex-Girlfriend Recalls Friendship with the 'Enchanting, Playful' Royal

Ray Bellisario/Popperfoto/Getty Princess Margaret

Princess Margaret is often portrayed as haughty and aloof, but to one of her son's former girlfriends, she became like a "surrogate mother."

Fashion guru and My Wardrobe Malfunction podcast host and writer Susannah Constantine dated David Armstrong-Jones, the Earl of Snowdon in the 1980s, getting to know Queen Elizabeth's late sister well.

"She was one of the most emotionally intelligent people I have ever met," Constantine, 58, who fronted TLC's Making Over America and What Not To Wear in the U.K., recalls.

Margaret would be on hand to talk about personal problems — and even her son David.

"I felt listened to by someone who I loved dearly and respected and admired," Constantine tells PEOPLE. "I was very lucky to have someone like that in my life."

Mike Lawn/Shutterstock Susannah Constantine

Margaret, who died in 2002, also came to her aid following a notorious moment when Constantine was dining at Windsor Castle with the rest of the royal family and the straps of her dress snapped during the soup course. A butler was ushered in with some safety pins.

Margaret "was fantastic and took me to the loo. She re-did [the pins] so that they weren't seen. We were laughing so much," she says.

Alan Davidson/Shutterstock Susannah Constantine and Princess Margaret in the 1980s

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The moment inspired Constantine's podcast My Wardrobe Malfunction, in which she interviews people about their life through their clothes – including the occasional embarrassing fashion faux pas. During the series she has chatted to her friends and prominent people from Elizabeth Hurley to Chic's Nile Rodgers and actress Kristin Scott Thomas and her former TV sidekick Trinny Woodall.

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Constantine's friendship with Margaret outlasted her relationship with David, and the royal even threw her an engagement party before her wedding to businessman Sten Bertelsen. The couple now has three children.

Margaret seated herself next to Bertelsen and "she was saying 'David and Susannah were so in love.' I was almost kicking her under the table asking her to stop. She did it all with a twinkle. Sten saw right through it. It was her mischievous side that was enchanting and playful and naughty. There aren't many mothers of ex-boyfriends who would do that," Constantine recalls.

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Kirstin Sinclair/Getty Queen Elizabeth and her nephew David Armstrong-Jones in 2018

Many people are now getting their perceptions of the royal family through The Crown —including a daunting scene showing former British Prime Minister Margaret Thatcher going to Balmoral and feeling discomfort at walking into the drawing room to see the royals all staring at her. But Constantine knows first-hand what that TV moment was really like.

She was there when Thatcher visited one summer and recalls a different tone. The party all headed to a tiny fishing bothy, or hut, where the royals were to have some tea. She remembers Thatcher being "incredibly bossy."

"The Queen would want to pour everyone's tea and I remember Margaret Thatcher almost booting her out of the way to pour the tea herself for everyone," she says. "She wanted to take control. That's the one thing that I remember."

Courtesy Susannah Constantine Susannah Constantine with podcast guest Elizabeth Hurley

Courtesy Susannah Constantine Susannah Constantine with podcast guest Nile Rogers

A new season of Constantine's shows premieres on May 9, and the host says she would "love to interview Oprah Winfrey."

"She is amazing and I love the way she dresses. She is simple and classy and it would be great to talk to her, "she adds.