"Whenever I speak to him, he always says 'why wasn't it me?'," she said.
She acknowledged aggravating features including alcohol and speed, asking the judge to consider home detention so Murphy could remain in rehabilitation, which he will need for the rest of his life.
"Speed combined with the alcohol was dangerous."
Crown prosecutor Emma Light said speed and alcohol, along with previous driving convictions, were aggravating features which meant a jail term was fitting to denounce the behaviour. She said a starting point needed to be three and half years' imprisonment.
Judge Hastings acknowledged the Morison and Murphy families were suffering immensely.
The court heard that on June 22, 2011 Murphy was drinking at home in Masterton in the morning and was picked by a friend, and continued drinking before heading home and consuming more alcohol.
About 8.50pm, Murphy headed to Eketahuna to visit a friend, resisting family trying to stop him from driving and trying to take his keys.
Murphy's aunt had texted Mr Morison asking him to not let Murphy drive, when she found out he had arrived there.
Soon after, the pair left to drive to Masterton but did not make it as Murphy lost control of the car on a "moderate bend" while travelling at an estimated speed of 129km/h, crossing the centre line, and slamming into a culvert and rolling.
His friend was found dead in the rear of the car.
"The force probably killed him instantly ... we will never know what Tom said to you ... you have suffered severe and lasting injuries," Judge Hastings said in sentencing.
Reading part of the victim statement reports from both families, he said, the date of the crash would never be forgotten by them all.
"What I can do as a judge and a father is acknowledge that grief."
The judge noted Murphy had 16 previous convictions, one for dangerous driving and driving while suspended and disqualified, and failing to stop for flashing lights, as well as failing to determine injury after a crash.
He sentenced him to 12 months' home detention, to be served at an Auckland "gated" rehabilitation facility.
He was also disqualified from driving for four years.