Her counsel, Brian Kilkelly, said Olliver had been visiting her partner's mother in Karitane.
As well as prescription drugs the defendant was taking for depression and anxiety, she had added methamphetamine and a class-C drug to the mix.
The results were pronounced.
On December 15, 2018 — a foggy night — Olliver began tail-gating a truck on State Highway 1.
Other motorists watched her weave around her lane, and often out of it.
The court heard the defendant travelled on the wrong side of the road for up to 400m at times, including around corners.
Other times, she almost left the road on the southbound side.
So concerned were other drivers that they put on their hazard lights to warn fellow road users.
Olliver was eventually pulled over in George St where officers noted her speech was slurred, her eyes were glazed and her balance was affected.
An impairment test clearly showed she should not have been behind the wheel.
Police said she was unable to follow even basic instructions.
Kilkelly said his client was struggling with her addiction at the time and had family matters in the background.
The court was told her situation had since settled and she was just weeks from giving birth.
Kilkelly said she was now clean of all drugs.
Olliver was sentenced to nine months' supervision, 100 hours' community work and was banned from driving for 15 months.
She was ordered to pay $757 for her blood-test analysis.
