In fact, she feels "physically sick" when she thinks about her fling with Gary that Geordie Shore fans watched unfold during series eight. Marnie and Gaz got together, following her romance with Scotty T, and enjoyed a fling before he decided to cool things off.
Looking back now, Marnie has said if there was one thing she could take back... it would be sleeping with Gary.
Speaking to the Daily Mail, Marnie revealed: "If I'm honest, I feel physically sick with what happened with Gary. If I could go back in time that would be the one thing I would change. It makes me sick up when I think about it."
She then shared her views on Charlotte and Gary's on/off romance that has made headlines the last few months. The co-stars who have been linked since they first started out on Geordie Shore seemed to pick up their relationship and fans had hoped we would see the couple make things official.
However, Charlotte has insisted she and Gary were 'never' together, despite seeming closer in recent months, and she recently confirmed she is single. Charlotte recently explained she and Gary could never have worked because of her trust issues and him signing up for the new series of Ex On The Beach.
Charlotte had told Reveal if Gary had stayed away from other girls on the dating show, she would have '100 percent committed' to him. However, reports claim Gary bedded Jem Lucy, as well as Charlotte Dawson and Jess Hayes.
Charlotte has now said things are completely over between herself and Gary. She recently explained: "I thought that maybe it was going somewhere. We'd spent quite a lot of time together he stayed at mine the night before he flew to Ex On The Beach... We'd had a lot of conversations where he had led me to believe that nothing was going to happen.
"It's something that I'm going to stay well away from and well out of. I don't want much to do with it at all."
It sounds like Marnie is all for Charlotte stepping away from Gaz, as she believes Charlotte is "too good" for him.
Marnie added: "I do think Charlotte can find someone nicer. I have heard the rumours and it's very unfortunate if it's all true. I'm not a fan of Gary... 100%. Gary as affected her confidence and I don't know why Charlotte got that involved with him.
"I feel like she put up a massive wall. She was confident and she was doing her own thing and I don't feel like she was that into him and he just sucked her back in. He's definitely manipulative."
However, Gary has responded to the drama surrounding himself and Charlotte lately and assured fans there are "two sides to every story."
He recently tweeted: "2 sides to every story remember that... I have found out a lot of important stuff over the last few weeks.. I'll explain all soon."
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