Alice Uden was sentenced by Judge Steven Sharpe in a Laramie County courthouse.
Jurors found Uden guilty of murder in the second degree in May after she testified that she shot then-husband Ronald Holtz, 25, in defense of their daughter -- a toddler at the time.
"He was very angry," Uden said on the stand. "He said, 'I'm gonna kill her."
Uden said her husband was enraged when the child began to cry, so she tried to stop him from hurting the 2-year-old. She grabbed a gun.
"He knocked me down and ran into her bedroom," she said. "I followed right behind him and shot him in the back of the head.
Uden was arrested in Chadwick in the fall of last year, along with her current husband, 72-year-old Gerald Uden, who pleaded guilty to the murders of his wife and two children in Wyoming in 1980.
The couple had been living in Christian County together for years. Sheriff Joey Kyle told KOLR 10 at the time of the arrests that they'd long been suspected in their respective cases.
"How do you sleep at night when you are lying next to a murderer? I guess because you are one yourself," Kyle said in 2013.
Gerald Uden is already serving a life sentence.
Copyright 2015 Nexstar Broadcasting, Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.