She told the High Court on Monday that Law thought she had been leaking stories to the media.
“To have the man you love think you’re leaking stories is awful,” she said.
“Our relationship was ruined for many years.”
In 2002, when Iris, their middle child, was 2 years old, she was taken to hospital after picking up an ecstasy tablet and putting it in her mouth during a family day at Soho House, a private members’ club.
A story describing the aftermath of the incident is among the 11 articles at the heart of Frost’s claim.
It included “accurate and very specific” details about how Law planned to sue the club, how their daughter’s brain was scanned and her stomach pumped in hospital and the strain it caused in their marriage, which Frost insists could only have come from voicemail interception.
The actress left the court in tears after recalling how she had been branded a bad mother as a result of the accident.
She sobbed as she insisted that it was not her fault, telling the judge she felt “amazing” that she had noticed the toddler pick up the tablet and “reacted in the perfect motherly way”, taking her to hospital.
“The next morning, I woke up to all this chatter, chatter, chatter,” she told the court, describing how photographers were on her doorstep.
“They were already saying it was my fault she had taken ecstasy... the newspapers were saying I was a bad mother, which was the worst thing anyone could say,” she said.
“Thank God I did notice it… It was on the floor. It was so humiliating. People thought I’d done this and I hadn’t. It made me so ill.”
Frost said the incident had come to publicly define her relationship with her daughter.
“They talk about the girl who took the ecstasy,” she sobbed. “My daughter knows, she knows. She’s held her head up high and she’s labelled with that.”
Frost was so upset that she asked the judge for a break, exiting the court before he had left the room.
‘A private medical matter’
Her claim also involves an unpublished story concerning her ectopic pregnancy and termination in 2003.
Frost claims the details contained in the article could only have been obtained from doctors.
Asked if she could have provided the information herself, she replied: “Oh my goodness, never”, adding that she was “shocked and appalled” at the time that anyone had known about such a private medical matter.
The actress, wearing a black top and blazer, was supported in court by her son, Finlay Munro Kemp, 35, whom she shares with her first husband, Spandau Ballet guitarist Gary Kemp.
She became emotional as soon as she took the oath, apologising to the judge and explaining that she was “really nervous”.
Frost told the judge that she did not have time to read all the articles included in her claim at the time as she was busy bringing up her children.
She explained that she suffered from severe post-natal depression and that the articles did not help her mental state.
Frost said it cost £1000 ($2290) to speak to lawyers and complain about any specific article and she simply could not afford it.
“Sometimes I want to complain but it’s too much money,” she said.
‘I am not a part of this plot’
Associated has argued that Frost’s claim cannot succeed as it was brought too late, arguing that it was “overwhelmingly likely” that she “knew or could, as a matter of basic inference, have known” that she had a worthwhile claim before the cut-off date of October 2016.
Antony White KC, for the publisher, showed Frost various emails sent between her and Dr Evan Harris, a member of the claimants’ legal research team, that he said demonstrated she must have known she had a claim.
But Frost insisted that she did not understand what the emails meant, that she was “confused and overwhelmed” and that it was all just “hot air”.
“I am not a player in this play, I am not a part of this plot,” she said.
“I’m just an innocent person hacked and victimised by the Mail.”
In some of the emails, Frost appeared to suggest that she would speak to supermodel Kate Moss, a close friend, with a view to bringing her into the claim.
But in court she repeatedly denied that she had tried to bring Moss on board.
“I would never use my friendship of a million years to bring Kate into a case,” she said. “Kate has her own lawyer that she always, always, always would go to.”
‘Claims wholly without any foundation’
White described Frost’s claims as “wholly without any foundation in the evidence before the court”, adding that they were “based entirely on spurious and/or discredited information”, with the articles instead “sourced entirely legitimately”.
He added: “Ms Frost’s circle was known to be ‘leaky’ in the period when her marriage to Jude Law was in difficulty, and this and their subsequent divorce was frequently being reported in the media”.
Associated is a subsidiary of Daily Mail and General Trust, Lord Rothermere’s holding company, which has agreed to acquire The Telegraph for £500m ($1.145m).
The proposed takeover is expected to face regulatory scrutiny in the coming weeks.
The hearing continues.
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