how to keep good attitude and make self happy everyday?

I have posted several times about my problems at work here. The turth is in this group I have been denied any growth opportunity. I think this is the bottomline why I am not happy. However, sometimes I feel better and can keep a calm and good attitude. Sometimes I feel lousy and act like a bee to sting and I only sting the high level managers since I believe they are the reason I am not happy. Well you can imagine the results...