The Essex star, who was dumped by Lydia earlier this year, was told by pal Tommy Mallet on Wednesday night's (20 July) episode that Lydia had smooched a Welshman while on a night out in Palma.
Arg replied: "It's just part and parcel of when you break up with someone. You'll hear about them. When you break up and you don't speak for a while and you hear they've been with this person or they're seeing someone else or dating, it's never easy to hear.
"She knows fully well that will get back to me. Yeah, I've been with girls and stuff the last few months but I made sure nothing too close to home. It's not the first time. How many times have we been on breaks and I've found out she's been with someone or done this or that? I've been there and done it many times.
"It's not the end of the world. It's just shame everything has happened. It's just sad, isn't it? And it's all my fault. But it's just funny how things work out, isn't it?"
Lydia opened up about her mystery man after Pete Wicks said he'd seen two men leaving her hotel room at 11am one morning. He had told the boys Chloe Lewis was there as well.
"Can we just clear this up now?" said Lydia. "Me and Chloe had partied with these boys. I smooched one of them.
"We were so drunk we went, 'Right, let's go home.' We got in bed – crashed in my bed – and in the morning the boys came down and asked if we wanted to go to breakfast. The one I smooched and one of his mates. I gave him a kiss on the cheek, my one took my number – result! – and we went down for breakfast.
"So Pete obviously saw them knocking and probably heard me and [Chloe] having a conversation. At the end of the day, people will gossip and spread things. I put my hands up and say, 'I smooched a very good looking Welsh man and I have no regrets!'"
Lydia added: "I'm not with James. It's his fault we broke up all those months ago. I'm single and enjoying life."
Lydia split from Arg following the series 17 finale in March. Neither has revealed the exact reason for the split but it's alleged to be down to Arg's excessive partying. Lydia has only said she felt very let down by him.
In a confrontation on the beach in Majorca last week, Lydia had told Arg: "I just think moving on from now I deeply don't want us to ever be friends. You're not the kind of person I want to be in my life. My life is my life now, and I'm getting on with it, we'll keep it that we're strangers. We will just walk past each other and that's how I would like it. I don't want to know you anymore."
TOWIE continues Sunday at 10pm on ITVBe.
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