"Huge congrats to @leemeadofficial on your new series regular role in BBC's Casualty," she wrote on Twitter. "We are very proud of you. Den & Betsy x"
The couple, who have a three-year-old daughter Betsy together, decided to split up this summer after four years of marriage.
"They're going their separate ways," an insider told The Sun. "It's very sad but they have grown apart and fallen out of love."
Denise, 39, and Lee, 32, cited their busy work schedules as a reason for their split, according to the newspaper.
Over the past few months, the couple had not had much chance to see each other, with Denise promoting Strictly Come Dancing and hosting her Magic FM radio show in the UK, and Lee busy pursuing stardom in Los Angeles and attending auditions.
After a brief spell in the US, Lee returned to London in May but by then the distance had proved too much and the couple's relationship had been under strain.
Denise has previously described them as being "like passing ships in the night " because of their busy careers.
"To be honest, it is really difficult," she told Now magazine. "We just haven't seen each other. I started on Strictly in September and we've been like passing ships in the night. I'm not going to lie, it's been a massive strain on the relationship."
While Lee prepares himself for his new Casualty role, Denise is in training for a charity Great Wall of China trek.
"Whenever I've done anything like this before I've always come back with a clear head, and the past few months haven't been easy," she told HELLO! in August. "It'll be going back to basics and then I'll come back with a clean slate ready to start again."
While the pair promised not to talk about their break up, what is clear is their united devotion and love for their daughter, which will be a comfort to Denise when she is completing the gruelling trek.
"I'm obviously going to miss Betsy so much, she came into work with me the other day at Magic and loved it.
"Lee is a fantastic father to Betsy and he's going to take time off work so he can look after her and she can spend time with her grandparents, I'm sure she'll be spoilt rotten which is lovely.
"This trip is basically a big thank you to the Royal Marsden and to the Edwards family for always being there for me. I just hope we can raise a lot of money and finish it in one piece."
Denise and Lee first met while filming the BBC talent show Any Dream Will Do in 2007 and married in April 2009. Their daughter Betsy was born on 1 May 2010.