'Married at First Sight 2019': John Aiken explains his tough love approach

Resident Married at First Sight expert John Aiken recently made headlines for his "bad cop" approach when dealing with participants face-to-face.

So, why does he go so hard?

The relationship guru dropped in to Talking Married on Wednesday night to explain his stern-talking reputation.

"Some like me, some hate me, but in this show we have to give out the tough love because they've got to learn along the way," he told the panel.

Most recently, we saw Aiken stop bride Susie mid-sentence during a commitment ceremony because her description of husband Billy was "doing [his] head in".

"It was one of those things where we've got really big personalities on the show and they're there to try and fall in love, but a lot of them are getting it wrong," he said.

"So we need to step up and be more directive, and intervene where we can so that they get what they're doing and do it different."

When it comes to the troubled new MAFS couple, Aiken did not hold back on Susie's problematic behaviour, which involved "cruel put downs, "eye rolling" and contempt".

"Unfortunately, you and Billy have a toxic fight style and when it goes, it goes pretty hard," he told Susie during the live broadcast.

His advice moving forward was to "learn to compromise more" and "to validate" each other during disagreements.

"Just to be able to say, 'Hey look, I get your point.' You don't always have to agree with it," he recommended.

"It's advice for everyone, really," he added.

It's common knowledge Season 6 of the social experiment has been clouded by infidelity.

First, we saw Ines and Sam go behind their partners' backs, and now Jessika and Dan have followed suit, sharing a cheeky kiss at this week's dinner party.

"I'm not happy about it, and neither are the other experts," said Aiken, who warned that "these two are running a very dangerous line."

Acknowledging the unpredictability of the experiment is gripping to viewers, Aiken said "those boundaries, when they get crossed it's very hard to watch" and defies the purpose of the experts' matchmaking.

"We don't put them together so that they can jump ship and cheat. So, this is something that we are disappointed in when we see it," he told the panel. 

See how the latest cheating scandal unfolds when Married at First Sight continues this Sunday on Nine at 7pm.

For more exclusives, tune in to 9Life every Wednesday at 9.00pm, right after MAFS.

You can also stream episodes of MAFS and Talking Married for free on 9Now.