Sandra Loveday was killed on Canterbury's Old West Coast Road last August when her vehicle was struck head on by a car driven by 15-year-old Ryan Eastwick.
She died at the scene, while Eastwick was taken to hospital in a critical condition.
He appeared in a wheelchair at sentencing on Tuesday and cried throughout the proceedings.
Justice Rachel Dunningham has given discounts for his age, health troubles and remorse and sentenced him to two years and eight months in prison.
Justice Dunningham has also disqualified him from holding a licence for two years following his release.
The Press reported Eastwick was driving on the wrong side of the road at 150km/h in an attempt to take his own life when he crashed head-on into Loveday's vehicle.
Hours earlier, Eastwick had been encouraged to commit suicide by another teen who had messaged him on Snapchat, The Press reported.
-Reporting RNZ and Star News
