The family of an Australian woman who was bludgeoned to death in London have said they will appeal after her former fiancee was given a minimum jail sentence of 17 years.

Roderick Deakin-White, 38, carried out the “horrendous and savage” attack on Amy Parsons, 35, while she was showering in the flat they shared in Whitechapel, east London.

She was left naked and bleeding to death after suffering “horrific injuries” to her head, face and brain during the attack on 25 April, a court heard.

Deakin-White was found guilty of her murder by a jury on 19 November.

Roderick Deakin-White murdered Amy Parsons on 25 April. Photograph: CPS/PA

Speaking after the sentencing, Parsons’ sister Eve, 40, said her family was “disappointed” by the length of the jail term and would be lodging an appeal.

“Based on what the judge had said, and that he had agreed with so many of the prosecutor’s points, we thought the sentence would be much higher.

“Seventeen years does not do her justice.”

Sentencing Deakin-White on Tuesday at Snaresbrook crown court to life, judge John Lafferty said Parsons was killed in a “most horrendous, savage and brutal way”.

Lafferty told Deakin-White: “Your view was that if you can’t have her, no one can have her, and you killed her.

“There is no sentence I can pass upon you today that will bring back Miss Parsons – a young, successful, vivacious and kind-hearted young woman, whose life was brutally taken by you.”

Deakin-White, who wore a suit in the dock, stared forward as his sentence was read out before being led away by guards.

During his trial, the court heard how Parsons, a personal assistant originally from Melbourne, had become increasingly unhappy with the couple’s relationship, particularly due to Deakin-White’s cross-dressing habits.

Prosecutor Gareth Patterson QC said at a previous hearing: “She was unhappy about this and this was something he had often wanted to do when they were intimate.”

He told jurors Deakin-White became angry and jealous after Parsons began a relationship with colleague James Saunders a few weeks before the killing.

The prosecutor said Deakin-White launched the attack after she told him she was leaving him.

“Unwilling to accept that she was going to leave him, he used a metal bar to hit her repeatedly around the head while she was showering in the Docklands flat which they shared,” Patterson said.

Deakin-White fled the flat before confessing to a friend, who persuaded him to hand himself in.

In interviews with police, Deakin-White admitted attacking her with a metal bar but denied murder, claiming it was an “accident”.

At his sentencing, Eve Parsons spoke of her family’s grief in a victim impact statement read out in court.

She described Amy Parsons as the “bright light” of the family and a “beautiful person”.

“Nothing could have prepared me to deal with this loss,” she said. “All of our family are as heartbroken as it is possible to be.”

Richard Carey-Hughes, mitigating, said Deakin-White had expressed remorse in the police station when he was recorded talking to himself, saying: “I feel like the nastiest person in the world. She would have been in so much pain.”

Lafferty sentenced Deakin-White to life with a minimum of 17 years in prison, reduced by 210 days which he has already served in custody.