Last autumn, Arg found himself on a downward spiral and was suspended from the ITVBe series before heading to rehab for treatment at Christmas.
Since then, the reality star has worked hard to clean up his act and has been hitting the gym and sticking to a healthy eating plan.
Last week, Arg was pictured looking remarkably thinner during a meal with some of his TOWIE co-stars.
Appearing on This Morning today (16 February), Lydia said all the cast are keeping their fingers crossed that he will be back on our screens soon.
"He's doing really well at the moment," Lydia said, when asked about Arg's "demons" by host Phillip Schofield.
"We're all hoping and praying he'll come back at some point during this series."
Lydia, who began dating Arg at school, was sat alongside co-star Elliott Wright and he too had nothing but praise for the popular Essex star.
"He's doing really well," Elliott revealed. "I see him in the gym every day and he's working really hard.
"He's an inspiration and has lost a lot of weight. I'm really proud of him.
"He was in a bad place and he's come through it really strong."
Jazz singer Arg first sparked concern in August when he failed to turn up for a scheduled flight to Majorca.
Lydia and her fellow TOWIE stars were frantic with worry and the Met Police launched a missing persons appeal. Thankfully, he was soon discovered asleep in a hotel room.
Weeks later, it was revealed Arg had got so drunk on a flight to Ibiza with the TOWIE cast that he vomited down his clothes.
After this, TOWIE bosses decided to suspend Arg from the show and he spent Christmas in rehab.
Arg has since enjoyed a healthy holiday in Hollywood where he spent time hiking through the hills.