In last night's episode (21 October), Arg told Tommy Mallet that with time, he is hoping Lydia would forgive him.
"All I need to do now is show Lydia that while she's not around, that I can look after myself and be responsible," he said. "She's reacted in a big way but we can see why, it's understandable. I don't think it's enough for us to not to be able to sort it out. Time's the best healer."
Lydia said she needed "time away" from Arg after becoming "frustrated" at his behaviour.
The final straw appeared to be over a recent night out where Arg lied about his whereabouts. He said he was going to stay at his mum's house, but he ended up crashing at Fran and Diags flat.
However, earlier in last night's show, Arg told Lewis Bloor that it's more than a little white lie. "I've had a bit of a bump in the road recently," said Arg, who entered rehab last Christmas for excessive partying. "I'm not worried about my recovery as such, I'm in a good place but they do affect Lydia badly.
"I know myself how far I've come in the last year and I do feel that I'm still on the right track, I'm going strong but if I do have bumps in the road, I'm just so petrified to tell her that I panic and maybe I tell a white lie or I'm a bit deceitful because I'm so scared of her reaction."
Arg later told his mum: "I've had a bit of a bump, a bit of a slip up and I lied. I shouldn't have done that.
"What I did was wrong. I can be a selfish person at times," he continued. "The thing that is more sad than anything is the fact that our relationship is strong. The only thing that's bringing us down is my recovery. I've just got to stay busy and stay strong."
Meanwhile, Lydia was in tears as she spoke about the state of her relationship to Tommy and his girlfriend Georgia Kousoulou, and said Arg needed to focus on his recovery.
"Whenever he has hiccups in his recovery, I can't do anything to make it better," Lydia said. "In the summer, me and James went through a very, very hard time. We were meant to go on holiday together and that all came crashing down because he made mistakes.
"I've never ever been so empty in my entire life. I honestly felt like I was walking around and there was nothing in me. I made a vow to myself that when we came back and we sat down and got back on track, I said to him, 'This will be the last time'. I can't cure him. He has to cure himself."
Tommy said: "Without you, then he's f**ked."
TOWIE airs every Sunday and Wednesday at 10pm on ITVBe.
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