The Strictly Come Dancing star, whose marriage break-up had been announced just one day earlier, stepped out in a black and white patterned short dress in London, and wore a wide-brimmed black hat that partially concealed her face.
This was the first time Denise has been spotted since her spokesperson formally announced the couple's spilt.
"Following continued speculation, Denise Van Outen and Lee Mead are sad to confirm they have decided to separate," said the formal statement. "The couple remain the best of friends, with their daughter Betsy as their number one priority."
Denise and Lee were last seen together earlier this month, taking three-year old Betsy on a family day out to the Tickety Toc launch party at Hamleys. The young couple were all smiles for the camera but it recently emerged that their conflicting work schedules had put a "massive strain" on their marriage.
There have been rumours surrounding the couple for months, not helped by the fact that Denise and Lee have not had the chance to see each other much. The mother-of-one was busy promoting Strictly Come Dancing and hosting her Magic FM radio show in the UK, while Lee was occupied with auditions in Los Angeles.
After a brief spell in the US, Lee returned to London in May but by then the distance had proved too much.
Reports that their marriage might be in trouble were reinforced when Denise was photographed holidaying alone over Easter in Dubai, without Lee. She soon put the rumours to rest, revealing that their decision not to employ a nanny meant that she and Lee were forced to holiday separately.
In the past Denise has described their relationship as being "like passing ships in the night" because of their busy careers.
"To be honest, it is really difficult," she said. "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."
The couple 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.