The email also claimed pictures of her semi-naked body would be posted on the internet and three people she loved, her son included, would receive bullets if she didn't give in to the emailer's demands.
The woman suggested he go for a run to sweat out the toxin, which he rejected. He emailed her again saying she would get a car if she followed his instructions.
Believing his life was in danger and because she didn't want their child to grow up fatherless she gave in to his demands.
According to the summary, further threatening emails were sent promising the woman large sums of money but none eventuated.
After yet another email in January 2016 the woman began to suspect it was her former partner sending them.
When she confronted him he denied knowing about them or photos she showed him, telling her he would make sure she never saw their son again.
When she attempted to push him away he knocked her to the ground.
Crown prosecutor Ngaroma Tahana said the man had showed no remorse, however lawyer Harry Edward argued the complete reverse was the case.
Describing the matter as "bizarre" Edward said the man had suffered considerable emotional upset and was in a new relationship with his partner.
"In terms of true criminality it is highly unlikely he will appear in court again on any matter," Edward claimed.
The man's current partner, who was in the public gallery, wept when the sentence was imposed.
The defendant pleaded guilty to both charges after receiving a sentence indication only days before his trial by jury was to begin in March.