Justice Dobson established a starting point for sentencing of five years and six months. He reduced that by three months because Paton was a victim of long-term domestic violence.
Paton's inability to appreciate the consequences of her actions with the knife had been dulled by her exposure to domestic violence, he said.
Justice Dobson said he noted the acceptance of violence in their relationship as expressed by witnesses.
One witness said she saw Paton "all bruised up" while another spoke of her "getting the bash'' as if such happenings represented normality.
Paton preferred to live in a violent relationship rather than to live without him.
That attitude was seriously wrong and impacted on their children.
Some might say Mr Teepa-Moon got what he deserved but that was not the case, the judge said.
Paton had taken the law into her own hands.
Mr Teepa-Moon's mother stated Paton was often the aggressor in the relationship.
Justice Dobson said he accepted the jury's decision, inherent in their verdict, that Paton had not acted in self-defence and used a disproportionate amount of violence.
The jury did not find Paton had murderous intent. But they rejected her claim that Mr Teepa-Moon was holding her knife-holding hand as the knife entered his neck.
Paton's offence was only "a very short way from murder'', he said.
She had issues with alcohol since her youth, and was considered to be at risk of re-offending and of causing harm to others.
Justice Dobson said Paton appeared to be remorseful about her predicament instead of "facing up'' and accepting her criminality.
Crown prosecutor Clayton Walker said Paton was angry on the night of Mr Teepa-Moon's death and wrongly believed he was sexually interested in another woman.
Paton grabbed two knifes, dropped one, and stabbed Mr Teepa-Moon with the other in the presence of other people.
Mr Teepa-Moon's family still suffered hurt and pain.
Counsel David Sharp said Paton felt a great sense of loss.
She acknowledged Mr Teepa-Moon's family was grief-stricken and appreciated them looking after her children.
Their relationship had moments of happiness but also the "spectre of domestic violence''.
Their type of dysfunctional relationship was all too common, said Mr Sharp.
