The reality stars quietly split following filming for series 17 and only made the break up public several weeks later. It wasn't, however, an amicable separation, with Lydia telling Arg this week she didn't even want to be friends.
Now, Arg is about to find out Lydia is well and truly over him.
In Wednesday night's (20 July) episode, Tommy Mallet breaks the news to Arg that Lydia's had a holiday romance while filming the new series in Majorca.
No doubt Arg is crushed as just this week he told Lydia he was sorry for things that had happened in the past, adding: "I do absolutely adore you. You know how much I love you."
Lydia and Arg had been on and off for seven years until their most recent split. Neither have given an exact reason for the break up but it's reported to have been sparked by Arg's alleged partying and alcohol issues.
A source told Reveal last week that both Lydia and Arg are trying to move on with their lives, saying: "[Lydia] has closure and she's the happiest she's ever been, and Ag has been really positive. He's not trying to win her back now, as he knows that won't happen.
"He's accepted it and is trying to move on."
Lydia and Arg met on Sunday night's episode, marking the first time they'd seen each other since the split. It wasn't the easiest of meetings for Arg, as Lydia told him he'd blown his chances with her and she no longer wanted him in her life.
"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. I would like you to stay away from my friends and family. Don't try to make my friends feel they're you're friends as they're not, they are here to support me," said Lydia.
"I don't want you to try to find out what I'm up to or say hello to me. 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."
She later tweeted she'd been "frustrated" by a focus on the negative reactions to her comments, saying she'd received plenty of positive remarks as well.
"Really frustrated by today's press. Yes I was harsh & some people have expressed that but equally I have received so much support from viewers. Everyone is entitled to express views on the situation. However highly frustrating when press are only printing the views against me."
TOWIE continues Wednesday at 10pm on ITVBe.
10 reasons why we want to be in TOWIE:
Follow us on Twitter @RevealMag for all your celeb, fashion and beauty news!