During last night's show (8 October), viewers saw Lauren confront Lewis about rumours that he cheated on her throughout the summer. Earlier, Lauren was left in tears after her best friend Vas J Morgan told her that Lewis had been unfaithful.
When Lauren confronted Lewis about the claims, he came clean to her about his infidelity.
"I kissed a girl in Marbella," he told her. "The girl that I kissed in Marbella I've got a lot of history with, and to be honest, she means a lot to me."
When Lauren asked Lewis about what happened in Dubai, he told her: "On my brother's 21st birthday I slept with a girl in Dubai."
An upset Lauren asked: "Does this girl that means a lot to you understand you had a girlfirend in the UK?"
In response, Lewis said: "I apologise about that. We were drunk."
But things between the pair turned sour and bitter pretty quickly...
"I'm enjoying my life. I'm young," Lewis continued. "It is what it is. I feel like this is probably the last time we're going to speak to each other. The times that I spent with you I did enjoy. We didn't see each other enough and it's difficult."
Lauren replied: "That's because I have a job. You wouldn't really know about that because you don't have a job or a career."
Lewis called Lauren's response "vindictive", then blasted at her: "You're double the age of a 16 year-old, probably plus. Go and get your passport, lets see how old you are. Who wants to go out with a f**king 40-year-old anyway."
A shocked Lauren hit back: "Are you joking? Oh f**k off you immature little jobless loser tw*t."
During the special spin-off show, TOWIE: All Back to Essex, hosted by Mark Wright and Denise Van Outen, Ferne said: "Lewis is mine and Billie's friend and I'm shocked. I'm absolutely shocked. I'm disgusted by his behaviour."
Billie added: "I've got to admit, it was a bit much, wasn't it? He was quite rude to Lauren. He was so cocky."
Still shocked by his behaviour, Ferne continued: "Lewis, we want to say, me and Billie are disappointed with you."
TOWIE continues on Sunday night on ITVBe.
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