A South Korean supermodel whose apparent suicide in Paris a week ago sent shockwaves through the fashion industry reached out to a friend for help with relationship problems a few hours before she was found dead.

It has emerged that Daul Kim, 20, the “Korean Kate Moss”, confided she had argued with her boyfriend but was afraid to leave him. The friend advised Kim to telephone her mother in Seoul. Kim ended the exchange of internet messages abruptly, saying she had to clean her flat.

Her body was discovered by the boyfriend soon afterwards on November 19. French police declared it a probable suicide but are still investigating. Last Wednesday, Kim’s agency said it appeared she had killed herself because of the pressures of work. “She was not able to live the normal life other girls did at her age,” said the agency in a statement. “We suspect that she felt confused and lost after reaching the top of her career.”

Her death was the second apparent suicide by a top model in Paris this year. In May, Lucy Gordon, a 28-year-old British model turned actress, was found hanged in her flat in a fashionable district on the Right Bank, where Kim lived.

Kim’s death appeared to be the latest in a string of Korean suicides that has included the country’s leading actress and a former president.

Joy Yoon, a friend of Kim and a fellow Korean, said despite her success on the catwalk, the 5ft 10in model was prey to dark moods and bouts of melancholy. “The loneliness she felt must have been suffocating,” she said. “Did her agencies really have her best interests at heart? I know she wanted stability and a somewhat normal life and even complained about it. Isn’t that a sign? A cry for help?”

Kim, who grew up in Seoul and Singapore, was discovered by Vogue Korea at the age of 17. In 2007 she broke on to the European fashion scene and never looked back.

She had worked for designers such as Dries Van Noten and Alexander McQueen, and had recently appeared in an advertisement for Christopher Kane’s Topshop line. Karl Lagerfeld described her as his new muse.

In fashion, it does not get much better than that.

Yet Kim was something of a rarity in a business known for its frivolity. According to JD Ferguson, a photographer, she was “a real thinker” with wit, zest for life and a passion for painting, film-making and Tolstoy. It set her apart on the catwalk and made her popular among other models.

Yale Breslin, a fashion writer, said “she definitely didn’t take herself too seriously”. Surrounded by friends, “the model persona came down”.

Behind the smile, however, was a troubled soul of which she gave glimpses in her internet diary. She often spoke poetically of the loneliness of the catwalk.

That theme also crops up in interviews with Kim, the last of which will feature in a tribute to her to be broadcast on a fashion channel in Korea.

She spoke of the difficulties she had at the start of her career because she was “different”. “Nobody understood me. I was a loner at school.”

On her internet blog, a big hit among teenagers, she would sometimes show the despair behind the glossy veneer of the high-earning, party-loving model.

“Freedom comes with such cost,” she wrote on October 15. “But is it even freedom?” she went on. “One could get numb living like this ... decadent nights to make up for the losses. But this endless loneliness. There must be something wrong from the core.”

Kim complained regularly of insomnia, exhaustion and how much she missed her mother. Friends suspected she was taking Adderall, a stimulant, to help her cope with a punishing routine of travel and public appearances.

In September, she wrote: “I wore high high heels and short short skirts to hide my depression.” A month later, she posted: “So many times I almost jumped but didn’t.”

An entry earlier this month reads: “Oh but how lonely it is. Then and now.”

A different side of Kim is on show in a video she made for New York Magazine, which had asked her to document life behind the catwalk. She tells a story about a model struggling to understand her accent.

“I was talking to a model and told her I was reading Hadji Murat by Tolstoy,” she began. “The girl was like, ‘Oh, you’re reading Toy Story’,” said Kim, adopting a southern drawl. “No,” said Kim, “Tolstoy. She’s like, ‘No, no, that’s not how you say it. It’s Toy Story.”

Her blog was flooded with tributes until her family shut it to the public last week. “She was a sweet, sweet girl,” wrote Ferguson, the photographer, on his blog. “Highly intelligent and a lot of fun.”

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