The former glamour model was heartbroken in May last year to discover Kieran had cheated on her with two friends – a betrayal made worse by the fact she had been pregnant and the time and had just discovered she was pregnant again.
But despite initially saying they were over, she forgave Kieran, helped him seek treatment for 'sex addiction' and renewed their vows in February.
Katie told the Evening Standard magazine that she knew Kieran would never cheat again as she's made it clear she won't be so forgiving in future: "If he so much as texts another woman, that's it, because that's how it all starts for him."
Katie, 36, said she isn't bothered what the public thinks about the situation or Kieran's 'sex addiction' diagnosis: "Everyone can have an opinion. I spoke to experts; I see how he's had to change and he knows there are no second chances."
She added: "I want this marriage to last. I don't want to get married again. I want this marriage to work and I want more children."
Katie also said she knew Kieran, 27, was staying with her for love – not for her massive bank balance. "I asked him if he was staying with me because I had money and fame or because he loved me and he said it was because he loved me. He wasn't lying."
Katie and Kieran have two children: Bunny, born in August, and Jett, who turns two this summer. Katie is also mum to son Harvey, 12, son Junior, nine, and daughter Princess, seven.
They renewed their wedding vows in West Sussex in February, a little over two years after they tied the knot on a Bahamas beach.
Katie recently told Australia's The Morning Show that the vow renewal was for Kieran, as he was the one who had broken his vows and promises by sleeping with other women behind her back.
She said: "Because he was a naughty boy, to move on we had to do our wedding vows. It was mainly for him, really, to commit to me. I didn't break my vows. He did. It was a really special day and I'm glad we did it. It was an evening thing, actually, not a day thing and it was perfect, really good."
Katie Price: All you need to know in less than two minutes!
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