Gary and Lillie had dated for over a year, before confirming their split in November last year. Despite reassuring fans their break up had been amicable at the time, it soon became clear things haven't been so friendly between the former flames.
Last night, they were both partying at Libertine Club, London and pictures have since surfaced of the pair arguing.
According to reports, Gaz and Lillie clashed over her new romance with Ex On The Beach star Stephen Bear. The model and Bear are now thought to be dating and seemed happy to flaunt their new romance all over Snapchat prior to heading out in London.
They had joined Lillie's pals Jasmin Walia and Kayleigh Morris, as well as Gaz, Jordan Davies and Ex On The Beach stars Jem Lucy and Liam Lewis at the same club.
Bear shared a photo of himself with Gaz, Jordan and Liam on Snapchat, before adding a clip of himself and Lillie kissing to his story.
A source told Daily Star Online: "Bear and Lillie were all over each other as soon as they walked in the club. They kept making out in front of Gaz – it was almost like they were trying to make a point."
"Bear has always been a wind-up merchant but even he was pushing his luck," they added. "Gaz and Lillie split six months ago but no one likes to see their ex move on in front of them."
Reveal has contacted reps for Gaz and Lillie.
Since Gary and Lillie split, he has been spotted appearing to mock her on social media. Following news that Lillie had signed to a celebrity management agency as a 'Fashion Designer, Model and Social Media Star', Gary hit out at his ex for being "embarrassing."
He then struck up a romance with his co-star and on/off flame Charlotte Crosby and later revealed Charlotte had been one of the reasons he chose to split with Lillie - thanks to their close friendship. Viewers recently watched Gaz struggle to balance being in a relationship and his closeness with Charlotte on series 12 of Geordie Shore.
Like Gaz, Charlotte has appeared to hit out at Lillie on several occasions. She has previously claimed that Gary thinks Lillie is a "fame-hungry sl*t."
Lillie, meanwhile, has kept silent following her break up with Gaz and chose not to retaliate or comment on Charlotte and Gary's romance. She did, however, hit back at claims she is "fame-hungry" after social media users began to label her it too, telling them: "Maybe you should respect I fell in love with a boy that was in the media eye... I kept it quiet for 6 months... As I didn't want the world knowing about my relationship but I had no choice."
"Unfortunately we broke up and I am the one that has acted like a grown up by not tweeting / selling a story / or speaking publicly about our separation. It wasn't something and isn't something I need to justify or speak about.
"The fact I haven't reacted to all the CHAZ remarks and nasty comments put my way is because I have some self respect and dignity and don't need to be nasty or lower myself to them / people."
Charlotte's comment that branded Lillie 'fame hungry' came after she appeared to confirm both Lillie and Gary for Ex On The Beach's new series.
She said she wasn't worried about Gary being reunited with Lillie during filming, as he "hates" her.
MTV had no comment to make on Charlotte's claim and the official lineup for the show is yet to be confirmed. However, Bear has also been linked to the new series - could that have been how he and Lillie first met?
Reports recently alleged Bear hooked up with Charlotte Dawson on the show. His ex-girlfriend Vicky Pattison appeared to hit out at Charlotte after finding out - she called Charlotte a "snake" for going there with her ex as they had been pals.
Again, MTV had no comment to make.
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