Kym, who has reportedly been spending time apart from her husband following their marital difficulties, took to Twitter to show her support.
"Hey everyone!!! Hope you're all good! @jamielomas1 debut tonight in @bbceastenders don't forget to tune in!!! X," posted the soap star, to which Jamie replied, writing, "thanks love x x".
The former Hollyoaks star will appear on screen as character Jake Stone, after it was announced in June that he would joing EastEnders.
"I have admired the show for many years and I can't wait to start working with such a strong cast of actors," said Jamie. "Jake Stone is a great character to play and I'm really looking forward to getting my teeth stuck into the role."
The television star has been busy filming for the show in London, which has meant spending time away from his wife and the couple's two-year-old daughter Polly, who are based in Manchester.
The couple are said to have put their family home in Worsley, Greater Manchester, up for sale, sparking rumours that their marriage was on the rocks.
"They've not split up but have been going through a tricky time — arguments and various other things," an insider told The Sun. "They have always had a tempestuous relationship and have been going through a hell of a lot."
This is not the first time that Kym and Jamie's marriage has been under strain. The couple tragically lost their son Archie Jay Lomas who was born prematurely in 2009. They also spent much time apart when Jamie travelled to Los Angeles to try and launch his acting career, which caused difficulties in their relationship.
The soap actors tied the know just eleven months ago in a star-studded ceremony that saw friends and fellow co-stars Michelle Keegan and Anthony Cotton in attendance.
Jamie has a son, Billy, from a previous relationship, while Kym has two children, Emily Mae and David Ryan, from her previous boyfriend Dave Cunliffe.