The glamour model admitted her stint on British reality TV show I'm A Celebrity... Get Me Out Of Here! had made her reconsider her future and realise she wanted to be alone.
She told presenters Ant McPartlin and Declan Donnelly: "Being inthe jungle has made me think. Alex? Well that's another thing. I have done a lot of reflection. It's best on my own. I realised I want to be on my own. I don't want a relationship. As soon as I came out I decided I am not with him.
"People will think it's harsh. But a lot of things have happened."
After quitting the camp, the first person Katie saw was close friend Michelle Heaton - a panellist on spin-off show I'm A Celebrity... Get Me Out Of Here Now! - who gave her pal a brief update on what she had missed.
Michelle said: "Alex was supposed to be coming over to propose to you. We think live on TV. Listen you know how we all feel. You need to get rid of him. I've told you."
Stunned Katie – who had supported Alex after revelations about his fetish for cross-dressing surfaced - said: "I tell you what. If he's done stories, that is it. Well, before I see him, I need to see everything."
Katie - who first entered the show in 2004, where she met now ex-husband Peter Andre - also admitted that one of her reasons was for quitting was the "torture" of so many memories coming back to her.
She explained: "The whole place reminded me of Pete from the moment I woke up, the afternoon to the moment I went to sleep, every second it was Pete, Pete, Pete.
"I was having closure but some of the reminders, it was cruel to do it to myself so I just didn't want to stay there.
"I have no regrets - it's the best thing I have done in the last seven months. It was a test to see how emotionally strong I was."
