I was the victim of a horrible preceptor as well. She didn't care, and half of the time I was pawned off to multiple other preceptors. I was happy when that happened because I learned more, but the others where disappointed and surprised at what I did not know. Since they were colleagues of my primary preceptor, I was the problem! I remember at week 5 thinking to myself, "How the heck am I going to do this?"
As yourself I was let go and devastated. I got another job a month later. I was nervous meeting my preceptor, but she took one look at me and said, "you are going to be great"! That was 10 months ago. Don't let one situation get you down.