Last March, Jayne Haworth, 50, held her birthday party at the Orchid Coffee Bar in the village of Longton, Lancashire - but there was a dispute over an unpaid £80 bill.
A month later, according to the Lancashire Evening Post, Haworth and her brother Mark Taylor, 53, bumped into the Orchid's owners, 53-year-old Linda Cartwright and her 19-year-old daughter Elizabeth at a local pub. Here, Haworth and Taylor shouted abuse at the Cartwrights, assaulted them and threatened them with violence. The police were called, and Haworth and Taylor were last week sentenced to 12 month conditional discharges and ordered to pay compensation.
Haworth and Taylor are now launching an appeal, and Taylor has also begun a private civil prosecution against Elizabeth Cartwright. But the story doesn't end there: while awaiting trial, Haworth opened her own rival coffee-shop, the vintage-themed Mad Hatters Tea Shop and Patisserie, nearby.
Responding to her supporters on Facebook, Mrs Cartwright says she's delighted by the guilty verdict, but that it's a "difficult situation". She adds: "It has been a nightmare... we are fighters and will carry on."
It does seem, though, as if there's something about sugary foods that leads to thoughts of revenge. This summer, outraged when chocolate manufacturer Cadbury was sold to America's Kraft, the founder's great-grand-daughter vowed to fight back. Felicity Loudon has now sold her £30 million mansion and is launching her own chocolate company.