Reflecting on the heartache in her new book, You've Got This, the 46-year-old - who reached the final alongside Kevin Clifton - explained: "If I'd done the show four years earlier, this wouldn't have happened. I wouldn't have walked away from my marriage."
WATCH: A look back at Louise and Jamie Redknapp's marriage
Louise added that taking part in the show, "simply wasn't worth putting anyone I loved or love through the heartache".
The mum of two shares sons Beau, 12, and Charley, 16, with her ex-husband. "I still wish I'd done things differently because I feel like I hurt a lot of people and I'll always be sorry for that," she added.
Her 20-year marriage to Jamie unravelled after her appearance on the hit BBC show. Since their separation in 2017, Louise and Jamie have remained on good terms - the former footballer has since found love with Swedish model Frida Andersson.
The singer was married to Jamie Redknapp for 20 years
Last year, during a candid chat with HELLO!, Louise confessed that she will always love her ex. "I still love him," she shared. "After 21 years together how could I not still love him?
"He's the father of my boys. Jamie's a great dad and is very proud that our sons love me so much. He has old-fashioned values and tells them to respect and love their mum."
You've Got This, £12.99, Amazon
They are co-parenting their two sons in a positive way. "We have a great system co-parenting them between us," she continued. "Our rule is that while one of us is working, the other is with them.
"We both want the kids all the time and encourage the other to go out so that we can have them. We share everything, too. On Christmas Day we do the presents together, they're from us both. Maybe this works now because neither of us is in a relationship, but I like to think it will always be like that."
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