back and not do it. but you can't. you can never go back. >> cynthia was convicted to first degree murder and sentenced to life without parole. what makes her situation unique is that prior to killing her husband, she worked as a prisons correction officer. >> a lost people will look at a woman in prison. they want to find an excuse. they want to say there's got to have been some provocation, some reason why she did such a terrible thing. in my case, that is not the case. my husband did not abuse me. he did not deserve what i did to him. we had been married 22 1/2 years and he was a good man. but my husband was clinically depressed pep was not an easy man to live with at that time. he was hard to please. >> when cynthia became involved with another man, she shot her husband and made it look like suicide. >> i wish i could go back. there's no way you can say sorry