Meanwhile, Stacey's ex-husband, Michael Goonan, is adamant she's lying about the affair, claiming she had already started covering her tracks before they attended the dinner party as a couple.
"Before we got to the dinner party, she goes, 'I think there's going to be a rumour coming out that I hooked up with Mikey - but we only went out for coffee.' I was wondering why she told me like that?" a perplexed Michael said on Married At First Sight's YouTube channel.
"It didn't add up. And I was like, well, if it didn't happen, it didn't happen. Then it came out that she slept with Mikey and I thought I'd give her the benefit of the doubt."
While he says he desperately wanted to believe the woman he fell in love with on the dating experiment, their flirty text messages were the final nail in the coffin.
"Then she says there's no messages, and out comes the phone," he said, still baffled she's still lying about sleeping with Mikey. "I still wanted to defend her and I think the world of her.
"But she made me grovel and jump through hoops and feel so guilty, she really crippled me. It was one of the hardest things I've ever had to face. Especially in front of everybody. It was gut-wrenching."
So what happened after the dinner party wrapped and the cameras stopped rolling? Michael told Nova 100’s Chrissie, Sam & Browny that he tried to chat with Stacey about these damaging allegations, however, she'd dug a hole too deep to claw her way out of.
"She continued to tell me it never happened. I said there was too much doubt for me to continue in this catastrophe so let’s just have a hug and I’ll see you later," he said. "But she said she didn't want to hug me... At the end of the day, I should be the one sort of stamping my feet and saying that I'm the victim."