Keith Wiens, 57, won't be eligible for parole until 2026 when he is 70.
Wiens maintained he shot Lynn Kalmring in self-defence in August 2011, saying the woman came at him with a knife but a jury rejected that claim after deliberating for just a few hours and declared him guilty of second-degree murder.
Justice Geoff Barrow called the shooting senseless, impulsive and fuelled by alcohol when he sentenced Wiens on Thursday.
The Crown was seeking a 15-year minimum sentence and the defence wanted a term of 10 to 12 years while the jury had recommended at least 20 years before parole eligibility.
The jury heard the couple fought over money for at least eight months before Wiens murdered Kalmring.
Her sister, Donna Irwin, said outside court that her family can now begin to move forward.
"It's a good day, we're all going to sleep well tonight, go back to our homes, try to pick up the pieces and get on with our lives because that's what Lynn would want," she said. (CKFR)
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