Nicole Scherzinger is "seething" with Lewis Hamilton after he partied with 10 girls in a hotel suite on Tuesday (10 July).
The racing driver had been out with rapper J. Cole before he headed back to London's Mayfair Hotel with a bevy of beauties and stayed up until 5.30am, and his girlfriend Scherzinger — who is a judge on the UK version of X Factor — is said to be furious with him.
A source said: "She is seething. She can't believe he would be so disrespectful to her in this way. It's not the kind of behaviour she expects from him. Lewis is in serious trouble.
"He wasn't thrilled when she accepted the X Factor job so there have been massive tensions. Now thing have reached crisis point. Nicole is demanding explanations and a discussion about their future."
Claudia Martinez and Emily Tudor, who were among the guests invited back to the hotel, reveal Hamilton was having so much fun at the penthouse suite in the venue he even sprayed the walls with champagne.
Tudor said: "It was huge, there was a kitchen, two bathrooms, two bedrooms and a huge lounge. Lots of people were chilling in the main room, people were smoking on the balcony. At one point, Lewis was spraying champagne all over the room like he had just won a race."
A source close to Scherzinger - who is currently in Los Angeles - told The Sun newspaper: "She is getting ready for a big role on UK X Factor and really doesn't need this. Their relationship is already under permanent strain because of hit jet-setting around the world with his job. She is fuming about this incident."