A man followed a drink-driver and flagged down a police car after the man "cowardly" fled a fatal crash scene.
Edgars Grisulis was jailed for nine years and nine months after killing Annette Booth when his car reversed into her at the Leicester bus stop.
On Wednesday, Leicester Crown Court heard how Ahmad Karwan followed the killer driver and flagged a police car.
Judge Martin Hurst said Grisulis, 27, had torn Mrs Booth's family apart with his "selfish and cowardly act".
Grisulis, a Latvian national, pleaded guilty to death by dangerous driving when he hit the 57-year-old on 29 September 2018.
The court heard how the father-of-one, of Saxby Street, Leicester, had borrowed his partner's Mercedes GLX after drinking.
'Coward's way out'
Blood taken from the inside of the car showed Grisulis had 144mg of alcohol in his bloodstream, the legal limit is 80mg.
As he drove towards the city centre on the A50 in Woodgate at a "terrifyingly high speed", his car "collided with the rear of a Nissan vehicle", driven by Mr Karwan.
Prosecutor Alex Wolfson said Mr Karwan knew Grisulis was going too fast, and was "bracing himself for the inevitable collision".
He got out of his car to confront Grisulis, but Grisulis "selected reverse gear" and began "swerving" across the carriageway.
He eventually hit Mrs Booth at the bus stop.
Mrs Booth's husband Stephen, who was with her at the bus stop, said: "All I can remember is the noise and the sound, and the carnage.
"At first I didn't realise that Annette had been hit, and the car sped off."
Mrs Booth, who had been due to become a grandmother the following month, later died at Nottingham Queen's Medical Centre.
Mr Wolfson said the Nissan driver "followed the defendant" and saw him abandon his car, with an unidentified passenger, under the archway of Grand Central Street.
Judge Hurst said: "You took the coward's way out, you threw your car into reverse and hurtled backwards a distance of 105m."
The judge said he was "weaving" along the carriageway "completely out of control", and he "mounted the pavement and collided at that spot with Annette Booth."
As part of their victim statements, a statement was read out by Mrs Booth's brother Michael Skeete.
It said: "I have watched my mum's health deteriorate, no mother should have to bury their child."
Her son Luke Skeete said: "My mum, my inspiration, my best friend, gone. Just like that without warning."
Her husband Stephen said: "The real truth is a massive part of me died with her that night.
"The only thing that keeps me going is our two sons and, of course, our new granddaughter."
Commenting on the sentence outside of court, Mr Booth said: "I feel like we've been served more of an injustice than justice as a family.
"He's 27 years old, once he turns 33 it's all going to be done and dusted, whereas we're living that life sentence."
Grisulis, who had previous driving convictions and did not have a British licence at the time of the incident, was also banned from driving for 14 years and 10 months.
In sentencing, Judge Hurst said Grisulis had a "cavalier disregard of the laws of this land and the appropriate way to drive".
"This family has been torn apart by your selfish and cowardly act," he said.
"You will be released from your sentence, they will continue to serve the life sentence you imposed on them."