L'Wren Scott's friends were concerned about her behaviour in the weeks leading up to her death.
The fashion designer - who was found hanged in her New York apartment yesterday (17.03.14) - had reportedly been ''acting strangely'' and was ''ducking phone calls'', sparking concern from her pals.
A source told the New York Post newspaper: ''They've known that something was going on, and it's been going on for at least a week.''
It had also been claimed the 49-year-old Scot - the long-term girlfriend of Rolling Stones singer Sir Mick Jagger - had been involved in a self-harm ''incident'' recently and had been suffering from depression.
A source is quoted by the MailOnline website as saying: ''L'Wren was really quite troubled and there were some issues over Mick and her standing in the family. It seems she suffered from depression.''
The insider went on to claim that L'Wren was unhappy Mick wouldn't marry her even though they had been together for 13 years, and she was said to be upset that his former spouse Jerry Hall didn't invite her to the baby shower she threw for the rocker's 42-year-old daughter Jade Jagger - his child with first wife Bianca Jagger - and her 21-year-old daughter Assisi, who are both pregnant.
The former model would regularly join Mick, 70, on the road with The Rolling Stones, but decided to remain in New York during his current run of shows.
The source said: ''She just wasn't well enough to go on tour with them.''
The Rolling Stones have cancelled their first gig on their Australian tour, which was due to take place in Perth tomorrow (19.03.14), in the wake of L'Wren's tragic passing.