It's so easy to be in bad mood. I think I've spent most of 2011 in an uncomfortable fretting state. Life's too short. So what if I don't know what this year will bring? So what if I can't see my path?
A couple of reliable routes to getting out of a mental negative rut:
Meditation, especially the mindfulness kind
Gratitude lists (top of today's is my remaining cat purring like an engine by my side)
The TED talk below is also pretty good at putting any gripes into perspective.