The Leader of Brentwood Borough Council's Conservative Group, Cllr Valerie Fletcher, has resigned.
The shock news came on Tuesday night with members of her group being informed by letter on Wednesday morning.
Speaking exclusively to This Is Essex Cllr Fletcher, a councillor for 20 years and a former Mayor, revealed that serving as a councillor no longer brought "much joy".
She said: "I entered local politics to represent residents, but unfortunately recently 'party politics' appears to have taken paramount hold of the motives of some within the chamber and I want to disassociate myself from this.
"Of course we all hold differing views. The world would be a pretty dull place if we all thought the same, but naively perhaps, I believe that political dogma should have no place in local government.
"My recent poor health, coupled with the death of three of my colleagues during an 11-month period, has made me re-evaluate a lot of things in my own life.
"Serving as a councillor no longer brings much joy to me, and therefore it must be time to move on."
Cllr Fletcher's resignation came just three weeks after Brentwood was rocked by a stormy council meeting which underlined the dissent between local Tories.
Conservative councillor Frank Kenny, was censured for accusing a member of using the internet to download inappropriate material while councillors agreed another motion by independent Tory, Cllr Tony Galbraith, for Brentwood council to investigate the dangers of religious cults.
In her resignation letter to Brentwood council chief executive, Colin Sivell, Cllr Fletcher, who is funds organiser for St Francis Hospice at Havering-atte-Bower, said she now intends to concentrate her energies there.
Liberal Democrat councillor Anne Long, said: "She has been caught between a rock and a hard place politically for some while now."
Deputy leader of the Conservative group, Cllr Richard Harrison, said: "Valerie will be very much missed and not easily replaced.
Moving on: Leader of Brentwood Borough Council Conservative group Valerie Fletcher this week shocked colleagues with the announcement of her resignation.
Picture: ROB BROWNE
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