Leandro, who broke up with Katie last month, has told Reveal that he called time on their relationship, rather than it being a mutual agreement.
The Argentinian model says: "From the day I met her until now, I don't think I knew the real Katie.
"She's not a big celebrity to me - I don't know why she's a celebrity at all. She has no talent.
"Katie destroys everything good that comes into her life - I'm so happy not to be with her anymore."
When Katie split with Leandro, she released a statement in which she claimed they had "run their course".
The pair had been dating for 20 months and Katie insisted they had both agreed to split.
But Leandro adds: "Leaving Katie was a difficult decision to make. Katie cried and begged me to stay. She then asked how many nights I was going for. I didn't know how to answer her."
Leandro also revealed how Katie told him about her shocking and explicit sex life with Alex and explained why he sympathises with her first husband, Peter Andre.
"Katie cared for Leo deeply but relationships end. It is time that they both moved on and if this is how Leo feels that should be easy for him."
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