The 36-year-old discovered Kieran, 27, was cheating in May this year, when she caught him and her best friend Jane Pountney, 49, kissing on a beach in Cape Verde.
After revealing his affair on Twitter, Katie later discovered he'd also been seeing her other friend 41-year-old Chrissy Thomas.
Since then Katie has stood by Kieran but regularly branded Jane a whore and Chrissy a slut.
But, despite everything, mum-of-five Katie said the experience has taught her a lot. She told Fabulous magazine: "I won't forgive [Kieran] and I won't forget.
"But I love him and I'm sticking by him. This has been the most hellish, insane, vile year of my life, but I've come out of it a better, stronger and more determined woman."
In her attempt to move on from the betrayal, Katie, Kieran and her children, Harvey, 12, Junior, nine, Princess Tiaamii, seven, Jett, one, and five-month-old Bunny, have had to move house.
She said: "Jane has nothing. Her marriage is over and she's hated by the man she actually thought loved her and wanted to marry her, Kieran.
"I even moved house because I couldn't bear to be in the house she'd been in [and] had sex with my husband in. But most of all I didn't want her to be able to picture us in our home."
After deciding to stand by him, Katie made Kieran take a lie detector test to get everything out in the open. He had therapy, but Katie said it was difficult because 'he wouldn't stop lying'.
She continued: "I still tell him our marriage is like a crumpled piece of white paper. No amount of ironing will get out those creases, but it's what we have.
"We went to zero and we can only start rebuilding. What I know now is he will never cheat again."
Katie also admitted her older children are aware of Kieran's affairs, adding: "The kids know he took a lie detector test. If I didn't tell them what was going on, they'd read about it online or hear it in the playground, and I want to be the one telling them the truth."
And, for now, Katie said she's happy with how things are going with Kierna, claiming he is now in control of his issues.
She said: "We still have a great sex life, but he is totally in control of everything. I'm happy about it. It's good between us now, we're getting there."