Tired and annoyed

Any one have advice as to finding another job in this *awesome* Michigan economy? I've been a psych nurse for almost 3 years. It's not me, I'm not enjoying it and where I work the supervisors don't help either. I've stayed longer than I've wanted but it was hard to find a job to begin with and now it's WAY worse. I want to enjoy what I'm doing, I don't feel I'm helping others the way I should. I try to excel and I always get slammed back down by my supervisor who isn't the most professional person in the world and has her people she *likes* and the people she *deals* with. I've put up with being there long enough I feel I just can't do it any more and I'm wasting my time doing something I don't necessarily love.

I applied for a Lead position in which on 2 people applied, alas I didn't get it (big surprise). I'm sorry, I've worked my arse off and then someone that didn't even really care if he applied got it. I feel now that was the final straw and I'm on a hunt for the job I long to have.

Do you think I'm stuck in Psych for only having Psych experience? Can I venture out? I would really love to do public health nursing.

Any advice?