After he strangled his wife, David Whitelegg set about organising his affairs. He gave away his cat.

He phoned a funeral parlour.

Then he wrote to his mother in England to admit responsibility for his wife’s death and apologise for having “stained” the family name.

Yet, when authorities found Anne Whitelegg’s body on the kitchen floor, her husband said she had fallen ill.

By 2014, the Whitelegg’s marriage was strained and Mrs Whitelegg was planning to leave.

Victoria’s Supreme Court heard Whitelegg – a 55-year-old former British Army major – lost his temper as the pair argued in their home in Wallan, north of Melbourne, on September 18.

A thin woman, Mrs Whitelegg was very drunk at the time her husband lost control and launched at her, the court heard.

“You attacked your wife when her ability to escape from you was compromised by the alcohol she had consumed,” Justice Jane Dixon told the former army major on Wednesday.

The court heard Whitelegg, became increasingly delusional before he murdered his wife and believed the Australian Defence Force and ASIO were stalking him and trying to force him out of the army.

He tried to take his own life soon after killing his wife, the court was told.

“You also said you missed your wife and she was your best friend,” Justice Dixon said.

Despite initially telling authorities his wife died unexpectedly, Whitelegg pleaded guilty to her murder.

He said he strangled her with his bare hands, but authorities believe the injuries to his wife’s neck are more consistent with him using a belt, the Supreme Court heard.

Whitelegg was sentenced to 18 years in jail on Wednesday.

He must serve at least 14 years behind bars before he is eligible for parole.

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