i've totally been there. actually, i was there a few days ago. winter is difficult, and my best friend and i were just discussing that maybe back in the day, humans hibernated in spurts during the winter. most mammals do it - sleep for a few days, come out and eat on a slightly warmer day, and then sleep for a few more. bears are just about the only ones that klonk out all winter long. i think humans just aren't meant to be up and about the whole season, and i've said many times during bouts of winter depression that i just feel like hibernating.

hope it gets better for you - sometimes getting a full spectrum light bulb or two in the house helps. you can pick them up at any hardware store on the way home from work. disney movies help too :)