I hate to say it, but if you defend yourself with lethal force, do not talk to the cops. I repeat DO NOT TALK TO THE COPS .
Request council and call your nearest loved one to get an attorney for you. Even if you are completely justified, the statements you make can (and almost always will) be used against you.
How does this apply here? Her lawyer would have made sure the statement was simple and to the point -- emphasized the immenent danger and noted the regret for loss of life. Instead, she gave too much information and now opens the door for second guessing, by unfortunately, the prosecution.
This advice is not from me, it is from the attorney who gave a short lecture at my CCW class (mandated by VA). No matter how hard it is for you, shut up, accept the ride to the police station, and let a lawyer sort it out. That's what they do and it can be the difference between getting a medal and 5 years for manslaughter.
jh