Dannii Minogue's former boyfriend "ruined" their relationship because he was insecure and jealous.

Kris Smith

Kris Smith

The 'This Is It' hitmaker was in a relationship with model Kris Smith - the father of her six-year-old son Ethan - for four years until 2012 and the 38-year-old former rugby player admits he has never believed he was "good enough" for his girlfriends.

Kris - who has been single since splitting from model Maddy King late last year after two years together - is currently competing on the Australian version of 'I'm A Celebrity... Get Me Out Of Here!' and was asked by his campmate Natalie Bassingthwaighte why he doesn't have a girlfriend.

He said: "I think I have ruined a lot of them. I'm just insecure and jealous ... not any more but I was because I was insecure. I never believed I was good enough

"I was really short and heavy as a kid. I always still see that. With age and growing up, I always had that little demon in my head that I was still that little fat kid."

And he later reflected on how his insecurities meant he had always pushed people away as he was convinced he would get hurt.

He said: "I would never let people get too close, I would push them away before they could hurt me because I was always thinking they would hurt me and I would never give them an honest chance to really know me."

But Kris hasn't given up on finding love and is keen to have more kids in the future.

He said: "I'd love more, I'm one of three boys, I'd like more kids. I've always wanted a family of two or three."

And the hunky star is pleased he and the 45-year-old beauty are able to work together to raise their son.

He said: "There's no real secret to [how we do it], Dannii and I committed to having a child together and we fulfilled that commitment.

"We've done exactly that and we're going to make sure he has the best quality of life and the best two parents he could ever wish for. If that's in separate houses, so be it."