London - Mariah Carey's jealousy is reportedly partly to blame for her and Nick Cannon's split.
The 44-year-old singer is said to have trust issues with her spouse - with whom she has four-year-old twins Moroccan and Monroe - and believes that he might be cheating on her whilst he is away working.
A source told RadarOnline: "Mariah thinks that when Nick travels that he cheats on her! Mariah is super jealous and things are clearly not good between them."
Nick confirmed on Thursday he and Mariah - whom he married in 2008 - have been living in separate houses for a while now but he denied infidelity had anything to do with their split.
He added: "My main focus is my kids."
However, it is believed their marriage started crumbling in March after Nick revealed he'd previously slept with five famous women, including Kim Kardashian, during an appearance on a US radio show.
Friends of the pair also believe they fell out after Mariah encouraged him to give up some of his work projects.
A source previously said: "It has a lot to do with Nick's career choices. He does not have to work, but he's been throwing himself into gigs and projects.
"She has tried and tried to get him to stay home more, but he always uses work as an excuse.
"When she points out that, financially, he does not need to be working as much as he does, it p****s him off and pushes him farther away. He hates when people assume he's living off her money."
Meanwhile, it is believed Mariah and Nick are currently in talks with their lawyers over a custody agreement for their children, as well as a property settlement.