Arg entered rehab last Christmas due to excessive partying, where he turned his life around and underwent a healthier lifestyle to win back his childhood sweetheart Lydia.
But during Sunday's episode, Lydia got upset after revealing Arg had been drinking again, while also admitting they had fallen out after a row.
In a heart-to-heart, Arg promised to change, telling Lydia: "I won't drink again."
Now, speaking in a new video on the TOWIE website, Arg revealed that he has had "a few slips ups". He said: "I've got to make these changes and continue my progress that I've made so far. I've had a few slip ups recently so I've just got to nip it in the bud.
"The plan going forward is to go through with what I said I've done: Motivation, get myself back in the gym, eat healthy and make more of an effort around the house."
Arg also said that he needs to work on improving his relationship with Lydia: "[I need to] make more effort with Lydia in regards to the relationship and do some nice things, start being more of an adult and more responsible. I'm confident in myself. I've come this far from where I was, and today to what I was in November is a completely different person.
"I suppose there are some insecurities that made a bit of issue but I suppose it's nothing we can't sort out."
TOWIE airs every Wednesday and Sunday at 10pm on ITVBe.
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