L'Wren Scott's death postpones Rolling Stones tour

Mick Jagger paid poignant tribute to his late companion, designer L'Wren Scott, on Tuesday, calling her his "lover and best friend" and saying he was struggling to understand why she might have taken her own life.

Jagger posted the message on his Facebook page as the Rolling Stones cancelled their seven-date tour of Australia and New Zealand, 14 on Fire, in the wake of Scott's death. The noted fashion designer was found dead Monday in her Manhattan apartment, an apparent suicide.

"I am still struggling to understand how my lover and best friend could end her life in this tragic way," Jagger wrote.

"We spent many wonderful years together and had made a great life for ourselves. She had great presence and her talent was much admired, not least by me."

He added: "I have been touched by the tributes that people have paid to her, and also the personal messages of support that I have received.

"I will never forget her."

Jagger was believed to be on his way to New York after hearing the news in Australia. The band issued a statement expressing regret that the tour was being postponed.

• L'Wren Scott, designer to Hollywood stars, found dead

Meanwhile, details emerged in Britain about financial troubles that Scott's eponymous label had been experiencing. Last month the designer canceled her London Fashion Week show, due to reported production delays.

Accounts filed by Scott's LS Fashion Ltd. in London show the company had liabilities that exceeded assets by 4.24 million (about $5.9 million US) as of Dec. 31, 2012. The company's long and short-term debts totalled 6.75 million against assets, capital and reserves of 2.51 million, according to the accounts, which were filed in October.

That news raised questions about whether Scott's label, popular on Hollywood red carpets, would now be able to survive. Steven Frumkin, dean of business and technology at the Fashion Institute of Technology in New York, said that was an open question, but that despite the company's difficulties, the brand could survive with skillful marketing.

He said it was crucial that the label also stake a claim to a wide audience, as Scott did in a recent collaboration with Banana Republic, and not just go after the high end of the market. Scott's designs have been popular with celebrities like Madonna, Oprah Winfrey, Tina Fey, Amy Adams, Nicole Kidman and first lady Michelle Obama.

Prominent fashion writer Robin Givhan noted that with a private company, it's impossible to know what the future holds. But she suggested that survival could be a challenge for the label, since it was "still quite young in its development and with a very limited audience. It certainly was not a household name." She added that the fashion line was "based on a particular aesthetic sensibility that was quite personal."

Model-turned-designer

Scott was adopted by a Mormon couple and grew up in small-town Utah. She made her way to Paris after high school where, aided by her 6'3" height (some say it was 6'4") and striking looks, she found work as a model for some prominent photographers.

• L'Wren Scott tributes pour in as celebrities pay respect

But she became more interested in working with clothes than modelling them, and eventually made her name as a top stylist in Los Angeles and a costume designer for films including Ocean's 13.

In 2006, Scott founded her label, with an initial collection based on the little black dress. She became known for designs that had a vintage feel and bared little skin, such as her famous "headmistress" dress prim, with three-quarter sleeves, but also close-fitting and stylish.