Judge Susan Thomas said that on the night of the final between the All Blacks and France, Bachop was commentating at a pub and he and his partner had been drinking.
As they were walking along Victoria St past the Wellington Central police station, he grabbed Belle by the arm, before pulling her by the hair.
A member of the public tried to intervene, but he was pushed away by Bachop just as police arrived.
The former New Zealand Colts, Western Samoa and All Blacks player then became verbally abusive to police, before physically resisting arrest.
He was arrested and taken into custody, where police found a small amount of cannabis, as well as a pipe on him.
Yesterday, the court heard how both Bachop and Belle believed he was guiding her, and he did not intend to hurt her.
In a victim impact statement, Belle said "valuable lessons have been learned and [our] relationship is even stronger".
Belle and Bachop each have three children from previous relationships, and Belle - who entered and left the court yesterday holding Bachop's hand - is now pregnant with their first child together.
But Judge Thomas said the witness had "significant concerns" as he followed the pair and was shaken by the incident.
Bachop had written a letter to the judge accepting irresponsible behaviour and accepted that at his age he should know better.
In sentencing Bachop, Judge Thomas said she had received positive references from many people about his character.
Bachop, who now works as a youth coaching co-ordinator for the Wellington Rugby Board and Northern Wellington rugby club, had already paid a $500 donation to Women's Refuge and was having counselling for drug and alcohol issues and taking a Living without Violence course.
His lawyer, Val Nisbet, argued for all four charges to be discharged without conviction, but Judge Thomas said she did not believe having convictions for assault would outweigh the seriousness of the crime.
However, she said travel could be a problem if Bachop was convicted for the possession of cannabis and believed the charge outweighed the seriousness of the crime.
Outside court, Bachop and his partner did not comment.
Bachop initially had name suppression but did not pursue it at a December hearing.
He said then, through Mr Nisbet, that he was not pursuing name suppression because he wanted to prevent any potentially negative impact on other former All Blacks.
Bachop initially pleaded not guilty but last month changed his plea.
