I agree it is a bad situation all the way around and it is a shame that this nurse will have to live with the fact that she killed a person with her own hands. That being said, just because she was calm and collected right after the incident does not mean anything. If you take 100 people and put them in the same stressful situation you will get 100 different reactions and different ways of dealing with things after the fact. I would imagine her being an ER nurse plays a huge part in her calm appearance after something like that. I have never worked in the ER before, but I imagine that if you FREAK OUT every time you are under stress that you wont last very long there. Her mind might have been conditioned to detach itself from feelings when she is under extreme circumstances, and to remain detached for ....... who knows..... 14 hours post-incident, or more. If she was just getting off work I bet her mind was still in ER mode and after, what did it say?, 30 years of that I imagine she has a pretty high tolerance for stress.
I agree that the family of the "victim" for lack of a better word, will probably sue her for wrongful death if they have the financial means. That is a loop hole within the system that is a sad reality. I do, however, only looking at the media rendition of this case, think that she was well within her rights of self preservation. It is not her fault that the guy was unable to defend himself after he attacked her in her own home.
I also dont think that it gives nurses a bad name in the least bit. She was attacked and she was able to overcome the enemy, after working a 12,24 whatever hour shift and maintain her calm demeanor. I dont think that the media is out to get nurses. The public perception of the RN is quite a good one, and rightfully so. The media, and I think they know this, would regret trying to defame this nurse or the profession because of something that appears to be as clear cut as this situation. That would be a bad move. Not that the media is immune from making bad moves..... heavens knows..... but in this particular case I dont think they will turn it into a circus. The chances are that she would be and is regarded as a hero more than as a criminal. It is impossible to judge her or her actions without being in her shoes. You might react in a similar way, who knows, unless you were put in that situation you have no business second guessing her.