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As the fashion and entertainment world copes with the shocking news that L’Wren Scott died Monday morning, those closest to her are attempting to piece together what drove the acclaimed designer and longtime partner of Mick Jagger to apparently take her own life.

According to a source connected to the 6-foot-3 fashionista, Scott, 49, had been deeply troubled and struggling with both personal and professional problems for the last couple of years, which caused concern for the pair’s very tight circle of friends. A perfectionist with her work, Scott also wanted nothing more than to keep her 13-year relationship with Jagger strong, the source added.

“L’Wren loved him so deeply, she never wanted to hurt him,” a source told FOX411. “She never, ever wanted to use his name to promote her business or seem like she was using him for her own profit. L’Wren just really loved him and was terrified at the idea of losing him or letting him down.”

We are assured, however, that the two were “very much together” at the time of her death, despite the ups and downs that come with such a high-profile romance. Jagger’s rep called reports that the couple had recently split “a horrible and inaccurate piece of gossip during this very tragic time for Mick.” The star canceled his Wednesday concert in Perth, Australia, in the wake of Scott’s death, a rep for the Rolling Stones announced.

Our source tells us it was some overwhelming issues with her top-notch fashion label that sent her down a final spiral. According to business records on file in Britain, as Scott’s business LS Fashion Ltd. operated from a London base, the design company had an October balance sheet stating that it was $5.9 million in debt in 2012 after closing 2011’s fiscal year $4.2 million in red. The balance sheet also indicates that more than $1.7 million was owed to creditors within one year and a significant $7.6 million due after that.

The financial woes were said to have been escalating for some time, and last month Scott pulled her London Fashion Week show. Publicly, the reason was a result of “production delays in key show and couture pieces,” but murmurs of business issues beyond Scott’s control circled.

“L’Wren really felt the pressure to succeed and having to be something all the time until, I guess, she couldn’t fake it anymore,” one person of note observed. “So many people wanted a piece of her. So many people had betrayed her personally and professionally; she didn’t know who to trust anymore.”

We're told that Scott felt extreme angst and personally responsible for all investors and creditors and people owed money, and she was not willing to simply walk away. She was also gravely concerned about her image in the fashion industry, and the potential years of litigation ahead upset her.

"She was so crushed by what had happened, and wanted to make things right for everyone,” the source said. “Also losing face in an industry she was so respected in was so hard for her to comprehend. She had to deal with all this and couldn't be on tour with Mick, which is where she really wanted to be."

A rep for Jagger, currently on tour with the Rolling Stones in Australia, said the rock icon was “completely shocked and devastated” by Scott’s death. Another source connected to the singer also told us that Jagger’s state of torment was “beyond belief.”

“I don’t think he’ll ever get over her,” said the source.

The adopted daughter of Mormon parents, Scott grew up in a small Utah town and started modeling as a teen after being discovered by famed fashion photographer Bruce Weber. After being somewhat deterred by the shallow treatment of models, Scott moved into designing and styling, eventually launching her first collection in 2006. She has since outfitted a vast array of A-list names including Madonna, Angelina Jolie and Nicole Kidman.

“L’Wren was an artist in the true sense of the word. She was very talented, very creative, but very soft and sensitive. It can seem like you have everything, but nothing at the same time,” added an insider. “But no one can believe she actually did it.”

Jagger’s rep did not respond to a request for further comment.

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