Kate Moss dumped Nikolai Von Bismarck after he refused to curb his party lifestyle.
The 42-year-old supermodel recently called time on her romance with her 29-year-old lover following a series of "volcanic rows", and insiders claim she grew increasingly frustrated with his "wild" behaviour.
A source said: "Nik refused to curb his wild lifestyle.
"Everyone knows that Kate loves to party, but Nik struggled to keep up without going overboard."
Nikolai's strained relationship with the British beauty's 14-year-old daughter Lila - who she has with ex-boyfriend Jefferson Hack - was also a factor in the split, with the pair regularly clashing and the aristocrat even turning off the Wi-Fi to annoy the teenager.
The source said: "Kate joked it was like having two kids, but obviously Lila is her priority."
And pals find the timing of the split interesting, as it came shortly after it was revealed Kate and estranged husband Jamie Hince have "quietly" agreed the terms of her divorce, a year after they split.
The source added: "Most of her friends saw Nik as a distraction while Kate was going through her break-up with Jamie, so it's interesting they've called it quits as soon as the divorce was finalised."
While Kate's friends are relieved she has split from Nikolai, they are concerned she will still have a change of heart.
The insider told Grazia magazine: "Kate has never really been on her own so friends hope she doesn't get back with Nik out of habit."
It was previously claimed Lila had grown increasingly unhappy with Nikolai's presence in their house, prompting Kate to have second thoughts about her relationship.
A source said: "Nikolai and Lila used to argue sometimes and it was always over petty stuff. He once switched the Wi-Fi off to annoy Lila after an argument so she couldn't use her phone and go on Snapchat and Instagram. Towards the end Lila did not approve of Nikolai and did not really like it when he was around.
"[Lila] is the most important person in Kate's life and Kate picked up on that. She has told her friends that she was aware that Nikolai was having an adverse effect on her relationship with her daughter and that was a massive factor in her decision to end it."