The former glamour model turned businesswoman, 37, also compared herself and Peter to Angelina Jolie and Brad Pitt.
In an interview with The Sun's Fabulous magazine, Katie says that while they've moved on, the public hasn't and are still "obsessed" with them.
She says: "We've both moved on, but we're like Brad Pitt and Angelina Jolie - everyone is obsessed with our exes.
"That is in the past for both of us now."
Mum-of-five Katie also revealed she's backing her ex to win Strictly, but won't be tuning in.
She says: "I think Peter will be brilliant because he's a great dancer and he'll want everyone to see that. I'd tell anyone to put a bet on him because I think he's going to win it.
"I'm not going to be sitting next to Kieran on the sofa watching Pete. So no, I'm not going to be watching it."
Katie also admits she has "always wanted to do" the show herself. Fingers crossed for next year!
She and Peter wed in 2005 after falling in love on I'm A Celebrity... Get Me Out Of Here!, but their marriage ended four years later.
They had two children together, Junior, 10 and Princess, eight. She also has Harvey, 11, from her previous relationship with footballer Dwight Yorke.
Katie is now married to Kieran Hayler, who she also has two children with.
The proud mum is often sharing stunning family snaps on Instagram with her 656,000 followers.
This weekend, the Celebrity Big Brother winner posted a photo of her youngest child, daughter Bunny, covered in fake tan!
She explained: "Bunny went to cuddle me and got fake tan on her."
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