The 40-year-old was struck down with tiredness and a cough after she contracted the virus over three weeks ago.
"F*** off covid!! I’m sick of being sick. I’m sick of you f***ing with my mental health I’m sick of being so bloody tired all time!,” she stormed.
Seeing the humorous side, the singer admitted she said she wanted a divorce from Covid-19 because she was "so used" to saying it over the years following three failed marriages.
"I’m sick of this cough and this mass feeling in my chest! I’m just sick of you!!!! I want a divorce!!!!
"Wait what sorry wrong drama just so use to saying that over the years!".
Kerry’s personal trainer fiancé Ryan has now tested negative for coronavirus.
She confessed it was only her left in the household suffering with the virus and waiting to test negative.
The Atomic Kitten star added: "I want you out of my life NOW F*** OFF but Ryan’s test is negative! Just me!!! Bloody great!!!"
Accompanied with the post, Kerry shared a letter from the NHS informing her she had tested positive for coronavirus.
Her second test was dated January 5, but it is almost a month since Kerry's first positive Covid-19 test was taken on December 15.
Last month, she took to social media to bite back at trolls accusing her of faking her illness.
"I can't believe I'm actually having to do this just to prove I had Covid," she wrote alongside a screenshot of a text message from the NHS confirming she had tested positive.
"The people who are saying that Celebs are being paid are fucking stupid idiots!!!! There people are clearly not bloody right in the head."
She added: "I've honestly never fely so poorly but happy to be through it now. Stay safe people xxx."