A married police officer accused of murdering his long-term lover has told a court their affair was "a little bubble of niceness".
Timothy Brehmer, a constable with Dorset Police, killed nurse Claire Parry in a pub car park on 9 May.
He is alleged to have strangled Mrs Parry after she messaged his wife revealing their affair of more than 10 years, Salisbury Crown Court heard.
Mr Brehmer, 41, of Hordle, Hampshire, admits manslaughter but denies murder.
During the coronavirus lockdown, the defendant told jurors, he had rarely seen Mrs Parry, who was married to another Dorset Police officer.
Describing the affair, Mr Brehmer said: "We didn't have to worry about the domestic things at home, you could be all of your good things, not your bad things, none of your vulnerabilities.
"It was a suspended state of your best self. It was an affair, that's what you have an affair for."
He added: "I didn't want to inadvertently destroy my family, which has happened anyway, so the relationship we had, Claire and I, it was compartmentalised as it was and had been for years.
"It was its own little bubble, a little bubble of niceness."
Mr Brehmer said Mrs Parry's husband had called him in March after becoming suspicious of their affair and she had sent him messages so they could keep their stories straight.
The defendant has previously said that Mrs Parry was injured accidentally outside the Horns Inn in West Parley, Dorset, when he tried to pull her out of his car after she used his phone to text his wife.
Mrs Parry, from Bournemouth, died in hospital the following day.
A post-mortem examination concluded the cause of death was a brain injury caused by compression of the neck
The trial continues.