A Stirling councillor has dramatically resigned from the SNP amid claims of bullying, sexism and party in-fighting.Bannockburn ward councillor Maureen Bennison - the partner of former Stirling MP Steven Paterson - resigned from the party on Monday night “with immediate effect”.While she intends to continue to represent the ward, her former SNP colleagues have called for her to stand down.In an official statement she said she had resigned “with regret”, adding she had “no further comment at the present time.”However, her letter to Councillor Farmer was far more explosive.In it she wrote: “This has been an extremely difficult decision, but it is the only principled course of action left to me in regrettable circumstances.“Since being elected.