On the night of July 29 he heard the service station alarm going off, and then saw the two men running away with cigarette packets.
He gave chase, but shortly afterwards collapsed with what they would later learn was a brain haemorrhage.
"His head just exploded in pain, and he felt like he was going to vomit," Deb said.
"I think it was just the stress of chasing them was just too much for him.
"He's really lucky to be alive."
Alan drove a concrete truck for work, but he's now in Ashburton Hospital, and may be transferred to Burwood Hospital to help with rehabilitation.
The damage from the haemorrhage has left him with difficulty with hand coordination, eating, and confusion about which words to use.
NZTA guidelines state that drivers of heavy vehicles should not drive for "at least" 12 months after a serious injury, and would need a neurological assessment before starting to drive again.
With Alan off work, Deb was now worried about how the family would get through financially.
They were midway through setting up a caravan cafe in front of their house.
They'd already paid to have the site prepared, but she didn't want to take on the loan for the caravan itself, as their finances were too uncertain.
"We've been planning it for four years now, and I'd bought things like the commercial oven for it.
"I've got the loan approved for the caravan, but now I can't in good conscience take the hours off work to run it, and pay back the loan.
"Because then if the food caravan didn't work out, I'd be even worse off, in more debt."
The family have set up a Givealittle page to help them fundraise for the caravan without debt.
A police spokesperson said they were continuing to make enquiries into the service station robbery.
Anyone with information should contact Methven Police Station.
