Barbara Hansen-Galyer was driving through Flat Bush to farewell her four grandchildren before they left on holiday on July 6.
She was at the intersection on Murphys Rd and Ormiston Rd when she saw a car hurtling towards her in the rearview mirror.
"He just smashed straight into the back of me, he didn't even brake," she said.
"It all happened so fast.
"I'm really bloody lucky that I didn't get hurt because he turned my station wagon into a bloody hatchback."
The "horrendous impact" crumpled the rear-end of her car with enough impact to damage the driver's seat.
Hansen-Galyer said she was devastated to lose the trustworthy car she had relied upon for almost two decades.
"It's never even broken down before."
Hansen-Galyer got out of the car and rang 111 - the operator asked her how the other driver was but it was impossible to check.
"I looked over and he was gone, he had tried to drive off," she said.
"One of the witnesses followed him down the road until his car putted out.
"She sent me a photo of his number plate ..."
Hansen-Galyer said she lost her leg above the knee to bone cancer when she was 16.
She said she found it difficult to ask for help but losing her car had had a huge impact on her life.
"It's like my life has come to a stop really," she said.
"I have never really been into asking people for help because I usually do things for myself.
"The other night I ran out of milk and it was like I can't even have a coffee because I can't go anywhere."
Hansen-Galyer said it had been depressing and she just wanted to get rid of the smashed car which still sits in the driveway.
She credited neighbours as being a huge support, one of whom has started a Givealittle page to rally funds for a new car. According to the fundraising page neither driver had insurance.
A police spokesman said a 28-year-old male had been summonsed to appear in the Manukau District Court later this month to face charges in relation to careless driving and excess breath alcohol.
