Her husband of seven years Vernon Kay has been caught sending sex texts and risque Twitter messages to five women since 2006.
And in a move that'll further devastate Tess, Now has uncovered a sixth girl and can reveal her naughty messages, sent earlier this month.
It's hard not to feel tremendous sympathy for the 38-year-old Strictly Come Dancing presenter, who first found out when the story broke in a tabloid.
In an interview with a glossy magazine given shortly before the scandal broke, she said: 'I know Vernon loves our family so much. I trust him totally.'
But she also hinted that their marriage wasn't as idyllic as people may think, adding: 'It's quite funny, people thinking we have it all - the perfect life. They should see us at 5.30am when Amber's crying and we're arguing over whose turn it is to go to her.'
The timing of the sex text scandal couldn't have been worse for Tess as on the very same day it broke she was promoting her new book The Baby Diaries, detailing her two pregnancies and dedicated to Vernon, 35, and their two daughters Phoebe, five, and Amber, nine months.
'Humiliated, degraded, cheapened - it's awful for Tess,' says one insider close to the star. 'It's so embarrassing for it all to come out now while she's saying in her book how wonderful her family life is.
'She always implicitly trusted Vernon not to stray - it never crossed her mind that he'd do anything.'
Tess and Vernon have been holed up at their home in Fulmer, Buckinghamshire, holding crisis talks.
She was forced to cancel two TV interviews promoting her new book this week because of the scandal and, according to those closest to her, 'can't face the public because of the humiliation'.
Meanwhile, it seemed like business as usual for Vernon, who didn't cancel his Radio 1 show on Saturday. The day before, he was linked to a number of blondes whom he receives Twitter updates from, although there's no suggestion at this stage that Vernon has sent any of them sex messages.
According to our sources, Tess is finding it very hard to believe that it was just texts and Twitter messages and nothing more. 'Vernon has broken the trust and she's asking if the texts mean he's had sex with any of these women,' says the insider.
'She's especially concerned that more women will come out of the woodwork, especially in the wake of the John Terry scandal. These girls know they can get hundreds of thousands of pounds for selling their stories.
'She doesn't know which way to turn, but there's no doubt that Vernon's in the last chance saloon. Tess is a strong woman and no Toni Poole - she won't just roll over and take it all.'
Vernon's confessed to contacting five girls the day after the story broke, but said it was harmless fun that had got out of hand, adding that it was more a case of 'showing off to the lads'.
Now reveals another girl!
We can reveal for the first time the identity of a sixth glamour girl who's been swapping saucy messages with Vernon. In the Twitter exchange, model Emma Murray calls Vernon 'goldenballs' after their flirting moves on from rude innuendo.
Now was told about Emma, 24, who's posed for lads' magazines and who works at the Manchester 235 Casino in the city centre, last week by a source who claimed she was on 'very friendly' terms with Vernon.
We found over a dozen Tweets that Emma had sent in response to Vernon's messages - which he'd kept private from his huge army of followers - over at least two months.
Mysteriously, a day after the story broke, Emma's Twitter account had been shut down and there was no sign of the messages.
When we tried to contact Emma, she failed to respond, so it's unclear how close the pair are, although she is good friends with Vernon's brother Steven, who she's also been Tweeting.
See the full story about Tess Daly and Vernon Kay in Now Magazine dated 22 February 2010 - out now!
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