The model and former sports star, who has 11-month-old son Ethan with Australia's Got Talent judge Minogue, allegedly told friends that he was sick of feeling like a member of her "staff" rather than her partner.
The couple were believed to have split after her Australia's Got Talent co-judge Kyle Sandilands alluded to it on his radio show last week but they then released a statement reading: "Thanks for your concern. We're happy to be back at home in Melbourne together as a family. We are committed to our relationship and [son] Ethan as always."
A source told The Daily Telegraph: "Kris felt that he had become an extension of Minogue's team of assistants. Someone she just dealt with, like a nanny or a secretary. Not one half of a loving relationship.
"Their conversations were cut down to the bone. The only thing they talk about is business and travel."
Rumours of relationship problems between Minogue and Smith first surfaced when she wrote about forgiveness on microblogging site Twitter. He responded with: "You don't know what you've got til it's gone."
Minogue's sister Kylie said of the couple: "I spoke to Dannii and she said they are happy together... her schedule is crazy like mine. I know how hard it is to see my boyfriend, but you just have to make time. It's good they are home together now."
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