Confused on what to do

I usually read the topics but this is my first one I started. I work night shift in a large teaching hospital which I do love. I didnt at first but I have grown to love it. I am going on 5 years now. I love most of my coworkers,I care about my patient however I am exhausted and burned out. The same nurse keep getting the good vacation dates,the schedules they want..most of us dont. Management never has a good thing to say..the morale of the place has been the lowest I have seen it. I dont understand what it takes for the charge nurse to one time say "Great Job everyone!"...its always something isnt done right. And right now staffing is terrible lately 8-9 pt per nurse bc they wont hire anyone. They however hire agency nurses for great positions that someone in the hospital would love to get a shot at. I began looking for work and was offered a great position elsewhere and I accepted it,however it is per diem for now. There is a possibility of part time and this is basically a step in the direction of a specialty field I wanted to be in for a long time. I can't work both jobs though..I am already exhausted in my current job. I work nights,3 kids and not a great support system with babysitting. This other position is whenever I want,days and very flexible plus better pay and it gives me the opportunity to make time to go back to school.Sorry about such a long post.