In short: she didn't take it very well.
Prior to his arrival, Jem had told her co-stars she was "dreading" being reunited with Hawley, especially as she is still in love with him despite him breaking her heart. She did, though, come face-to-face with him and Jem demanded answers from her ex-beau...
Jem and Hawley had dated for ten months, after first meeting in Ibiza. While he claims Jem has put his personal details on social media, she has accused Hawley of cheating on her.
Ahead of reuniting with Jem, Hawley claimed he still has "unfinished business" with her and confessed he does still love her.
"I want to know why she would put so much time and effort into trying to ruin's someone's life?" He said. "It's evil. It's definitely going to kick off, sh*t will hit the fan."
When he did approach Jem, Hawley told her that he had come on the show to prove a point that she is a "f**king snake." He said: "I've come here for some clarity on why you've tried to mug us off in front of the whole f**king world."
Jem hit back: "What, because I f**king told the world what you are? Because you f**ked me off."
"I'm not having it," she said. "I know for a fact that Hawley cheated on me. He sh*gged Gaz's ex behind my back and I want some f**king answers."
She asked Hawley: "So publicly you didn't humiliate me?" When he denied doing she, she fired back: "Don't make me f**king slap you Hawley."
Hawley then told Jem to "f**k off" and breaking down in tears, she stormed off. She said: "I can't handle it. I'm not even speaking to you."
Jem told the camera: "The thing that upsets me the most is that I love him so much still. I really f**king love him. I don't know why."
Hawley, meanwhile, said: "I always knew seeing Jemma was going to be hard, but I didn't know it was going to bring back emotions I thought were gone."
Things then got even more tense between the pair as Hawley found out Jem had slept with Gaz Beadle (his friend for over ten years) on their first night in the villa. Hawley criticised Gaz for having "no morals", but Gaz branded him a "hypocrite", claiming Hawley has slept with his ex in the past too.
Jem and Hawley did get the opportunity to clear the air, but their attempts of building bridges were thwarted by Jem's confession that she had slept with Hawley's best friend and Geordie Shore star Scotty T.
On hearing that, Hawley declared: "I'm going to make it my number one mission to f**k Jemma over."
Ex On The Beach continues Tuesday 30 August at 10pm on MTV.
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