Stop beating yourself up! I am sure you are a very safe nurse! Look on the bright side - getting out of the kaiser system was your saving grace.
Forget them, you don't need to be abused and treated like that. Hold your head up high, you will not be beaten - patients need you. You have to get real with yourself - contact your agency and try another hospital and put this behind you, I know it sounds easier than it looks (it hasn't helped with an earlier comment I made) however, what doesn't break us, makes us stronger.
Don't worry over spilt milk, there are more people worst off than us in this world - give a thought for those who are facing life threatening diseases or the soldiers who are on duty facing the enemy.
Best of Luck
You will survive!