Ayda Field Williams has said her husband Robbie Williams broke her heart by breaking up with her three times before the couple got married and had children.
The X Factor judge said watching the audition of one hopeful singer brought back the devastation she previously felt.
In scenes that will air on Sunday’s episode of the competition show, Field Williams will speak about her heartbreak while listening to 18-year-old Chloe Jane McAllister, from Northern Ireland, sing Jessie Ware’s Say You Love Me.
She says: “Rob put me through some, Rob dumped me three times. What a bad man, I know we’re all thinking it.”
After watching her performance, she adds: “I thought that was amazing and I felt the heartbreak.
“In fact I felt it so much that Rob will be sleeping on the couch tonight because it made me remember what an awful human he was to me.”
Williams, who is also a judge on the panel, says the performance also stirs up strong emotions for him.
He tells McAllister: “I’ve got a daughter and her name is Theodora Rose Williams and she’s five years old and she is my life and I go to piano lessons with her every Friday and I was thinking about you being that same person and learning your craft.
“I want to show the person who means the most to me in the world exactly what they can achieve when they put their mind to it and they practice because you’re the person I want my daughter to be like.”
The couple celebrated their eighth wedding anniversary in August and also have a son, Charlton.
Earlier this month they revealed they have welcomed a third child, a daughter given birth via surrogate, named Coco.
Other contestants hoping to impress the judges during the final round of auditions is Thomas Pound, 20.
The cleaner from South Wales gives the panel a rendition of Tina Turner’s Simply The Best but is sent away by judge Simon Cowell, who tells him he would rather see him perform in his drag queen alter ego.
Pound returns later in the show to perform Turner’s hit Proud Mary, this time dressed up as Lady Frieda Wilde, and alarms Williams by immediately jumping into the splits.
After the performance, Cowell says: “Thomas, or Lady Frieda, you’ve got balls.”
Other acts looking to score a place in the Six Chair Challenge, which will follow the auditions stage after it was announced bootcamp would be scrapped, include Blaise Duncan, 16, from Derby, who performs Enrique Iglesias’s Bailando and 18-year-old student Jon Guelas, from Cambridge, who hopes to dazzle with his version of Lukas Graham’s 7 Years, as well as Elliot Horne, 18, from Oxfordshire, who sings Shawn Mendes’s Lost In Japan.
Family gospel group ATTY, from Birmingham, also hope a Mendes track will secure them a spot in the next round, giving a performance of his single Mercy in the hopes of impressing the judges.
The X Factor is on ITV on Sunday at 8pm.