In a statement, she said: “As someone living with MS, I have the unquestionable right to decide when and how to share such sensitive details.
“Pursuing the claim was a necessary and principled step to protect that right, as well as my career and livelihood.”
Jarman said she regarded Spencer’s decision to agree a settlement as “a clear vindication” of her legal action and said she was “relieved” the matter would now come to a close.
Jarman began legal action against Spencer last October for the misuse of private information, accusing her of telling an array of friends and employees about the medical condition.
When Jarman lodged the claim, her diagnosis was still confidential. But she later claimed that she was forced to reveal she had MS in a high-profile newspaper interview to end gossip online and because she was concerned about the “loss of autonomy and control”.
Jarman said she had “worked very hard indeed” to keep the diagnosis hidden from many people she knew, including the Earl, 61, in the early days of their relationship.
Lady Spencer, a Canadian philanthropist, had robustly defended herself against the allegations, indicating that she was prepared to fight the claim at all costs, and was being represented by David Sherborne, Prince Harry’s barrister.
She accused the Earl of having an affair with Jarman and alleged that he had informed her by text message last March that their marriage was over, “completely refusing” to discuss it in person or even to provide an explanation – behaviour she said was “both cruel and inexplicable”.
Lady Spencer said Jarman’s decision to reveal her own diagnosis in an interview with MailOnline was “hopelessly inconsistent” with her claim that she wanted privacy and accused the archaeologist and Lord Spencer of attempting to “garner publicity for their relationship” in the press.
The Earl insisted that the Countess had ended the marriage, adding: “The notion that I would end my marriage by text is an absurd attempt to blacken my name”.
The settlement was revealed by Justice Peel, who is overseeing the Spencers’ separate financial remedy dispute.
A spokesman for Countess Spencer said: “Countess Spencer confirms that the legal proceedings brought against her by Cat Jarman have been resolved in an agreed settlement. Countess Spencer considers her position to have been fully vindicated.
“There was no admission of liability or wrongdoing... Countess Spencer sincerely hopes this will mark the end of the matter.”
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