Tuckervill, Salsa might be right. When I first moved to WA I would always go out to run and ride. I figured I liked rain (coming from Calif, I had no idea what I got myself in to!) and didn't mind cooler weather. My activity started becoming less frequent though the change was so subtle, I didn't recognize it. Before I knew it, I just wanted to sleep all the time.

What worked for me was forcing myself to get out. I'm stubborn and if I have a goal (weekly mileage or weekly workouts), I will make sure I accomplish it or else I feel like a failure. It's a mixed blessing because it gets me out but I quite often feel like a failure

Take care of yourself and I'm glad you are recognizing it for what it is. Hopefully it will either go away (in which case you'll know it's winter) or you'll be able to treat it.

Oh and since moving up to here, I gained maybe 25 lbs? It hasn't gone away yet. It needs to.