Yolanda Davis, 45, of Gary, was sentenced Monday, the Chicago Tribune reported.
Davis pleaded guilty last month to involuntary manslaughter in the March 2006 death of her boyfriend, Johnny Jackson.
She admitted she stabbed Jackson in the chest with a steak knife in his home after Jackson struck her in the face and lunged at her again during a fight.
Davis said she thought Jackson's injury was "only a scratch" and left the house, however, medical reports revealed she caused a tear in Jackson's heart, which resulted in fatal internal bleeding.
The newspaper said it is unclear whether Jackson is related to Gary's famed Jackson family, which includes pop stars Michael and Janet.