He then hit her in the head with an axe, before fleeing the South Rd home with the couple's 3-month-old son.
As his victim lay bleeding and unconscious on the floor, her 5-year-old son went to a neighbour to raise the alarm.
Ms Whiteman said if it wasn't for grandson's actions, her daughter would be dead.
"The only reason Folimatama isn't doing life for murder is because of that little boy."
The family lived in constant fear of Folimatama being released, and had installed security systems and begun training a German shepherd.
They also contemplated leaving the country, "because that is the only way we could live in some sort of peace".
"All that we have got is the hope he has a little bit of humanity in him."
Folimatama will appear before the New Zealand Parole Board, who will also hear from the victim's family two days later.
Following his May 2014 parole hearing, the board noted he received a "very good report" on completing a drug treatment programme, and had started a rehabilitation programme.
He had been approved for work outside the wire, and "in due course he should become eligible for Release to Work".
She hoped Folimatama would serve his full sentence, and his parole conditions would include not being able to reside in Dunedin where he could come in contact with her daughter.
"The thought of him living in Dunedin is untenable."
Ms Whiteman said her daughter, who late last year had a titanium plate inserted in her skull, was still "trying to get on with her life".
Her grandson who raised the alarm was now 9 and continued to be plagued with nightmares.
"He is at the age when he can comprehend it more, and is very nervous about being anywhere alone."
It was a similar feeling for the family.
"When you are a victim in New Zealand, your sentence is forever."
Mrs Whiteman, who campaigned for tougher penalties for offenders breaching protection orders, said those orders alongside non-contact and trespass orders were "all after the fact ... they are to punish the person for coming near you".
"Once he's free, there's nothing to stop him [finishing] what he started."
"We used to say to our daughter 'you aren't a victim, you are a survivor', but, to be honest, you are a victim forever. You are re-victimsed every time there is a parole hearing and you live in fear they are going to get out.
"There is no end to it."