"Delta would sit with her mouth open and Brian would spit into her mouth and Delta would spit back into his mouth.
"You would think they're all good. He's English and she's Australia's sweetheart, but at my place, (Sandilands makes spitting noise) 'I got her!' And I was like, is that love?"
Jackie O was not impressed, saying, "I think that's gross. I think I'd throw up if someone spat in my mouth."
Goodrem and McFadden started dating in 2004 after recording Almost Here which was released on the Aussie singer's Mistaken Identity album. They got engaged in 2007 in Bali but split four years later in 2011.
After breaking up, Goodrem told Vogue: "I was really unhappy and I didn't know how to get out. I learnt. I got there in the end," she said.
The former Neighbours star also spoke to 60 Minutes about the failed relationship.
"Do I wish that it ended earlier? Yes. Do I wish I had the courage to leave earlier? Yes, I do. I think what we came to is that we were very different people — extremely different people," Goodrem said.
After Goodrem's two interviews, McFadden tweeted: "Sometimes silence is golden. People love to try and deflect attention from their own downfalls onto others. Randomly want to thank (fiancee) Vogue Williams for making me the happiest man on the planet."
McFadden, 38, is currently dating a PE teacher named Danielle Parkinson. Goodrem has been linked to rock singer Matthew Copley but The Voice coach told InStyle Australia in April that she's keen to keep details of her dating life private.
"All I've kept saying is, 'I'm single and I'll let you know when I'm in a serious relationship.' And I will," she said.