The reality star is currently holidaying in the Indonesian island and didn't appear to show any signs of a break up as she documented her journey on Instagram and Snapchat.
She captioned one snap: "Good morning from Bali, the most magical place in the world."
Lydia's photo follows reports that she dumped Arg after it is thought he relapsed in his recovery over alleged "cocaine use".
A source told The Sun: "Lydia and Arg have broken up and it's for good this time. It happened because he relapsed. Lydia came home early from an event in London and found Arg a bit out of it. She's absolutely devastated."
Reveal have contacted their reps for comment.
Arg, meanwhile, has spent the past few weeks in boot camp as part of his new get fit mission to lose weight.
In series 17 of TOWIE, which wrapped up last month, Lydia and Arg made a vow to never break up again as they went house hunting in Essex.
Arg had said: "I just want it to be a family home. I want it to be a home that we will live in for the rest of our lives."
Lydia told him: "Let's just clear it up, when we say family home, with a family coming in like five years. Because we are doing this, though, getting a house together we need to make it a pact that we can never break up with each other again. I do think we're going to be insane parents."
The childhood sweethearts have had their fair share of break ups and make ups, most of which has been documented on the ITVBe reality show.
Series 16 last year was a very dramatic time for the couple after Lydia took time out of her relationship with Arg and cut off all contact after becoming "frustrated' with his behaviour when he relapsed on his road to recovery.
But they overcame their issues, and by the Christmas special they were loved up again, with Lydia jokingly saying she wanted a marriage proposal this year.
Arg was suspended from TOWIE in October 2014 and spent that Christmas in rehab to curb his partying habits.
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