Marnie had hit out at Jem and Jordan Davies in her weekly column for Star magazine, branding the pair "embarrassing" after seeing photos of Jem and Jordan hooking up.
She claimed that they are "desperate for fame", prompting Jem to ask Marnie: "What's your problem?"
Marnie had initially wrote: "I've seen some pictures of Jemma Lucy and Jordan Davies hooking up and all I can say is they get more embarrassing by the day. I don't think you could find two people who are more desperate for fame than this pair."
She added: "They're a match made in heaven."
Jem is currently holidaying in Ibiza with EOTB's Olivia Walsh, but she made sure to respond to Marnie on Twitter.
She tweeted: "Wtf?!!! What's your problem Marnie?!" Before adding: "FYI I regret those pics and was off my face but we all make mistakes don't we (sic)."
Jem wasn't the only one to hit back at Marnie, as Jordan responded on social media too.
He had tweeted: "Charming...Funny how you still wanted to go on holiday in secret behind your "on off flings" back #HoesAintLoyal."
Jordan also added on Snapchat: "I feel f**king s**t this morning. And to top it off, I've woken up to a lovely article from a certain Marnie G Shore calling me desperate and fame hungry.
"You wanted to go on holiday behind your on-off fling's back without nobody knowing. So before you keep slating, Marnie, just remember you had an on-off fling and wanted to go on holiday with me, so how does that make me desperate. Just saying."
When contacted by Reveal, a rep for Marnie had no comment to make.
Jordan and Marnie had been romantically linked earlier this year. Reports claimed the pair had been 'secretly texting' for months, before they stepped out on Valentines' Day for a date.
Since then, however, Marnie has ruled out any romance with Jordan. She insisted the pair are just friends, telling Mail Online: "He's just my friend. He's like a lovable brother or a gay best friend, except he's not gay. Romantically, I'm not interested. He's just a lovely boy and I enjoy his company."
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