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In the wake of fashion designer L'Wren Scott's death on Monday, speculation has run rampant about what may have led to her apparent suicide. Two prevailing theories: relationship and financial woes.

The New York Post alleges that Scott, 49, who was reportedly found hanged in her luxury Manhattan apartment, told a friend last week that boyfriend Mick Jagger, 70, had ended their 13-year relationship, a claim vehemently denied by his rep.

The split story "is 100 percent untrue," his spokeswoman said in a statement. "There is absolutely no basis in fact to this story. It is a horrible and inaccurate piece of gossip during this very tragic time for Mick."

The Rolling Stones frontman expressed his grief in an open letter on Tuesday.

"I am still struggling to understand how my lover and best friend could end her life in this tragic way," he wrote on his website, in a post simply titled "L'Wren." "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. 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."

Adds a source to E! News, ""They loved each other and were wonderful together. They had a very cool relationship and a deep respect for one another. They have been together forever, and there was no sign that things were ever changing in that regard."

Scott's business, however, was reportedly not going well. According to the BBC, her company was an estimated $6 million in debt.

"Everyone thought she had a perfect life, but when you would chat to her it was clear her life was far from it," a confidant tells the New York Daily News. "She told me, 'I think I worry too much.' She had a high-profile business with lots of buzz and lots of press but you didn't always see the money flowing in."

Scott, whose many admirers included longtime friend Nicole Kidman, Sarah Jessica Parker, Michelle Obama and Penelope Cruz, fell into modeling during the mid-80s when she met photographer Bruce Weber on a shoot in her native Utah.

The 6-foot-3 beauty, born Luann Bambrough, changed her name and embarked on a successful career in Paris before heading to Los Angeles in the '90s to become a fashion stylist.