The last we knew these two were friends - and Marnie even described Jordan as "like a brother" - but clearly something's amiss judging from today's war of words.
It started when Marnie took a swipe at Jordan and Ex On The Beach's Jem Lucy in her weekly column for Star magazine, branding them "embarrassing".
Marnie 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. They're a match made in heaven."
Jordan replied to Marnie via Twitter, saying: "Charming...Funny how you still wanted to go on holiday in secret behind your "on off flings" back #HoesAintLoyal."
He said the same thing on Snapchat, telling fans: "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."
A rep for Marnie had no comment to make.
Earlier this year, Marnie admitted she felt "guilty" for kissing Ex On The Beach star Jordan on a night out, because it had hurt Geordie Shore co-star Aaron Chalmers, although she wasn't dating Aaron at the time.
Marnie later told Star mag: "I felt really guilty [about kissing Jordan], but I didn't think [Aaron would] be that bothered. I've never seen that side to him. I was shocked. He wouldn't speak to me for about three weeks. We normally talk every day. It was so hard."
She also denied seeing Jordan as anything other than a friend, 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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