A devoted husband who strangled his wife because he could not cope with her descent into dementia has been jailed.

Malcolm Bearden, 79, made a pact with his wife Margaret, 78, that they would always care for each other and never allow them to go into a home.

The retired bus driver could not cope as she lost her memory and snapped after she ceased being able to recognise him.

He strangled her on the bed at the home where they had lived together for 50 years after she mistook him for a stranger and accused him of being a "dirty old man" when he asked her to get undressed for bed.

He was jailed for 12 months yesterday after a judge said he had a duty to uphold the sanctity of human life.

His son had sent a letter begging the judge to free him pleading: "I have lost my mother, I don't want to lose my father too." The family wept in the public gallery as he was jailed.

Bearden, of Churchfields, Wellington, Somerset, admitted manslaughter due to loss of control and was jailed for 12 months by Judge Graham Cottle at Exeter Crown Court.

The judge told him: "This case is unique and presents an agonising sentencing exercise and one which is likely to leave opinion divided.

"You had been married for 58 years, you met when you were 16 and were childhood sweethearts, married when you were 21, and it was a marriage characterised by mutual and deep devotion during which you brought up two children.

"In the latter years of her life she developed senile dementia and her condition deteriorated slowly to the extent where caring for her had become increasingly difficult.

"Her condition deteriorated to the extent she was no longer recognisable as the woman you had loved and cherished over the years." The court was told how Bearden turned down offers of help in order to care for his wife. But his stubborn refusal resulted in tragic consequences.

The judge said: "In your words, you snapped and you strangled her to death. I am sure that what you did will haunt you for the rest of your days.

"This was not a mercy killing nor was it close to an assisted suicide. It was the taking of a life by a man who had temporarily lost his self control of the wife he had loved for many years.

"To describe this case as tragic is a significant understatement but the principle of the sanctity of human life would be undermined if the prison sentence was suspended."

Michael Fitton, QC, defending, said the couple had made a pact that neither would allow the other to go into a home and so he had taken over the burden of running the house when she became wheelchair bound through arthritis and asthma.