Denise Van Outen has reportedly split from Lee Mead.
The couple - who have three-year-old daughter Betsy together - are said to have called time on their four-year marriage because they have "fallen out of love" after spending lengthy periods apart, and though they are upset about the separation, they have vowed to remain friends.
A source said: "The spark just faded after a while. It's very sad but they're still best mates and hope it will stay that way.
"There hasn't been a big blow out but they are now having a trial separation and coming to terms with going their separate ways.
"They hardly saw each other over the last nine months because of their work commitments. The distance had become too difficult to overcome. They had grown apart - and fallen out of love."
Lee, 32, is believed to have moved out of the north London home he shared with 39-year-old Denise - who he met when she presented 'Any Dream Will Do', the talent show on which he found fame - and their daughter, but will still be a frequent visitor.
The source added to The Sun newspaper: "Lee will still come to the house to look after Betsy because he and Denise still genuinely like each other even though their romantic relationship has broken down."
The couple's relationship has been the source of speculation for months after they were barely seen together, with Lee even missing his wife's appearance in the 'Strictly Come Dancing' final last year.
However, friends insist their problems have only surfaced in recent weeks.
The insider said: "When people first said there were strains int heir marriage 18 months ago it just wasn't true.
"People assumed because they don't appear in public together very often that something was wrong but that wasn't the case. They were happy and confident leading separate lives."
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