She was a fashion tycoon who made it in her 20s and 30s and lost it all in her 40s - the house, the butler, the housekeeper, the nanny, the places at a top London private school for her two children.
So it is all the more remarkable that Joan Burstein should decide to spend her middle age rebuilding the family fortunes with one of the riskiest business gambles imaginable. She set out to introduce the affluent fashion-buying public to designers untried on British shores, avoiding safe bets - "I could never do the ordinary," she says - and taking a gamble that she would always be able to pay the rent on her Mayfair shop.
It was thanks to Burstein, the country's first truly visionary fashion retailer, that Ralph Lauren, Calvin Klein, Donna Karan, Missoni and Armani got their first look-in in London, that raw British talent like Galliano and Christopher Kane got a leg-up straight from fashion school, and that way-out Japanese houses like Comme des Garcons got window space other retailers didn't dare accord them.
As well as getting in exclusive merchandise, Joan made shopping fun for the well-heeled, creating a clubby atmosphere in her one-room South Molton Street boutique, just off Oxford Street. "But I couldn't have done it without my husband," says the woman known to the London fashion world as Mrs B. That is B for Burstein and also for Browns, the fashion empire on South Molton Street.
"Everyone knew about me, he would tell me, but no-one knew about him," she says of Sidney, her husband of more than 60 years, who died last month at 93. Burstein finds herself in mourning at the very moment she is expected to put on a brave public face at the launch of an exhibition celebrating 40 years of Browns.
"I'm terrified," she confesses at her Hampstead home in the first interview she has given since Sidney's death, "but at the same time, I think he would be lapping it up. He was the business side, he made all the property deals that let us expand all over South Molton Street. I am glad there's a chance to pay tribute to him."
Burstein believes it was her husband's early prowess as a hawker of hosiery and underwear in the Ridley Road, in the East End, buying nylons on the black market during the war, which honed his acumen in launching a much posher business three decades later. "He was a market trader when we married in 1946, and I was working in a chemist's shop," she recalls.
The fact she was wearing Dior's New Look as a young bride was everything to do with taste and nothing to do with money. "My mother was a tailoress, but didn't have the money to dress me in designer clothes. However, her sisters, who were court dressmakers in Camden Town, where I was born, dressed me - they made my clothes, and my new look was a clever copy."
Sidney Burstein's ambition led them into real shops to sell his hosiery and underwear. "He was the buyer and I painted all the boxes puce-pink! But I liked meeting people and enjoyed selling; I was a very early working wife."
The Kingston shop, in southwest London, founded with Sidney's brother, expanded rapidly into an empire - Neatawear, the Topshop of its time. "It set the standard for being young and different, but we were overstretched. And in 1968 the bank wanted their money back," says Burstein. Going bust was something she took in her stride, quoting "survival" for her motivation for finding the courage to do it all over again - showing designs which were new and different, but at much higher prices. "I wanted to do what no-one else had done, and I was influenced by France and Italy. London had no designer boutiques except for Yves St Laurent's, selling only one label."
In the days before high-end, ready-to-wear shows, Burstein had to work hard to find extraordinary merchandise. "It was about sniffing designers out, having the right connections, travelling to America and beyond until people started coming to us."
Bold moves, like buying up the whole of John Galliano's graduate show, were not a risk from her point of view. "You couldn't not want it - and it didn't cost much to buy the whole lot. It was fabulous - sheer abandonment, just like Galliano himself."
As the gamble paid off, Browns colonised South Molton Street. "One ground-floor shop grew into five interconnecting townhouses on three floors, and then two shops opposite. And that was Sidney, making all the deals," she says.
A dedicated shoe store and bridal shop were followed by a breeding-ground for young designers: "Most of them started at Browns Focus before being eased across the road to the main store."
It has remained a family affair. "The children were 16 and 14 when they joined the business, and now my son is CEO and my daughter is creative director."
She is a member of St John's Wood Liberal Synagogue, a supporter of Jewish charities and says Sidney was as fierce a friend of Israel as she is, "even though he didn't do religion".
In her 84th year she is working as hard as ever. "Even while spending a lot of time with Sidney, who was ill for several months, I would go into the business every afternoon," she says. "I like being in control. I still sell and advise, I still want to be better all the time."
But she is also devoting time to staying fit and healthy and finds great solace in deadheading flowers on the terrace of her Hampstead home: "It's my therapy - keeping them healthy, seeing them come back into bloom."
And there is a pet project - persuading the designers who have formed Browns's past to recreate some of their iconic designs, putting out affordable but collectible limited edition pieces adapted from their archives for sale not only in London and online but in the new pop-up shops Browns has set up within luxury stores in Berlin, Dubai, Zurich and Geneva.
"Of course I won't get to have a piece," she sighs, but with a wardrobe by Jil Sander, Missoni, Lanvin and Marni, she is not feeling sorry for herself.