Lydia and Arg were dating when the show began - before various cheating rumours emerged, which resulted in the pair splitting. Earlier this year, Arg admitted in his book that he cheated on Lydia with former TOWIE star Amy Childs.
Speaking to us at Lauren Pope's InTheStyle.co.uk fashion launch, Lydia said: "I was really angry about it. It wasn't good to find out when everyone else it did it. It upset me."
She explained how she always had her suspicions that something went on between the pair: "I did suspect it. I did a big scene of it on the show and the whole public sided with Amy and I thought I was going crazy. That's what I founded hardest. They both knew it was true and let me go through it."
"I thought 'Oh God, I've turned in to this horrible possessive girlfriend' when deep down I was right. Amy isn't my friend and I haven't spoken to her."
Fans of the Essex-based reality show tuned in to see Lydia and Arg meet up for dinner in Marbella on Sunday's (22 June) show and the pretty fashionista explained that reading his autobiography 'Living It Arg' helped.
"A lot of his book is about me but I'm glad I read it before I went on TOWIE. It anwered a lot of questions and he does really apologise for it, which is nice. He doesn't hold back, he's very honest."
With Lydia now back on TOWIE, will she be hooking up with any of the current boys? Sadly, it doesn't look likely!
"A lot of the boys I have grown up with. I went to primary school with Tom Pearce and Ricky Rayment. I see them all as brothers. But that's not to say I would rule out a TOWIE romance, there's just no-one on the show at the moment."
Geordie Shore's Gaz Beadle recently got us wondering if he had a crush on Lydia after he tweeted her snap of her looking hot in a bikini, so we had to ask if there's anything likely to happen between the pair.
"Yeah I saw that too. I've only met Gaz once before at a party and he was a really funny guy. But right now, I'm not interested in anyone and I just want to be single."
Filming for series 12 started this week and Lydia admitted that she's pleased to have returned. "I'm really glad to be back and with all my friends and back in the hype of it."
She also confirmed that our favourite Essex mum, Debbie Bright, will be making an appearance. "Yes she is, she will start filming for this series. It's really exciting because obviously I love filming with my mum and we have a great relationship."
We can't wait to see these two back on our screens!
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