CLICK ON PHOTOS FOR FULL GALLERY
The Chelsea footballer was spotted kissing his former wife at her 28th birthday party on Friday, and he has told his friends he intends to remarry her.
They apparently spent the night together after the Geordie beauty's party at London's Sanderson hotel, which is said to have cost £20,000.
Fellow guests included Cheryl's Girls Aloud bandmates Nicola Roberts and Kimberley Walsh and her pal from the Black Eyed Peas, Will.i.am.
According to reports, Cheryl - who looked pretty in a Stella McCartney dress and new blonde hairstyle – started secretly dating Ashley again three months ago.
They resumed contact long before her unsuccessful stint as a judge of the American X Factor, covertly meeting at his brother Matty's house.
Then after she returned to Britain, the pop star spent the night at their former marital home Godalming, Surrey.
A source told The Daily Mirror: "They got back together because they want children and they could not live without each other."
"They've never been happier.
"Ashley has got his wife back, and this time it’s for keeps.
"He has learned from his mistakes and knows he messed up but he’s promised Cheryl he will change."
It's been nine months since the couple divorced. Back then, the singer spoke about the end of her marriage during an emotional interview with Piers Morgan.
"Looking back on it, I feel numb. We had a great marriage and a fantastic wedding day but I don't know where it went wrong," she told the interviewer.
Visibly upset, she added: "I just don’t have the answers. None. He was my best friend and we were so happy. Our marriage was so strong.
"Part of me will always love him. We used to be so close but I was heartbroken."