The 28-year-old didn't hold back in the post where he also slammed producers, going as far to say he'd been "f***ed in the backside" in how he'd been portrayed.
But what was perhaps most interesting was his mother claiming Cathy is a "paid actress".
“What a terrible edit, f**k it I’m calling mum," he jokingly posted before writing in the comments, "F**k me dead on a Devon sandwich. [Producers] left out the [entire] lunch and I had the old hugs and kisses back [from Cathy afterwards].
"MAFS (has) f***ed me in the backside... Should’ve went on Survivor... I’ll never do a TV show again.”
His mother, Mandy Manning, added to the comments, "Actress from hell."
A viewer wrote, "So we now know they break up for good lol [thank you]!" Mandy replied, saying, "She was a paid actress... employed by the producers."
A friend added, "We did well to keep our gobs shut until now! Cathy is playing a victim! The tears, definitely trying to get on Home and Away. She's playing her role well, sort of."
The Facebook post comes after Josh changed his relationship to single earlier this week.
Daily Mail reports the reality star graduated from university with a degree in performing arts and moved to Sydney to pursue a career in show business.
Meanwhile, Cathy has denied she has been acting on MAFS, telling the NZ Herald, "I can confirm I'm not an actor. I've changed careers many times [since university]."
While Cathy does have a YouTube account, it's unclear if she's actually landed any acting gigs since moving to Sydney.
During Monday night's episode of MAFS, Cathy once again faced off with Josh's mother during his hometown stay.
Mandy continued to bring up old issues that the couple faced and Josh didn't defend his 'wife' and instead threw her under the bus multiple times.
Cathy was clearly upset after the meeting, telling the cameras, "I get it, that's your son. My valid reasoning is not enough for her because her son takes first priority."
"And she was bringing up things that are just going to reignite feelings of anger and resentment for Josh."
Josh spoke about the homestay to Talking Married's Shelly Horton after the show aired, saying, “I kept saying I’m gonna stay positive, tomorrow we’re riding bikes, we’re going to the beach I’ll crack a few funnies hopefully she’ll smile and this will turn around."
“We went to home stays on kind of like a bad foot because she felt that I’d already made up my mind. She was off me, as soon as we got to home stays she wasn’t there, she didn’t want to be there – I could tell.
“You can only try so much when someone doesn’t want to be there and she didn’t.”
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