Winter Blues

So the kids went back to school yesterday. I'm hoping for a return to my version of the norm, but I fear I'm already dragging my heels into 2013. In my defence, I've been ill, but I do annoy myself with how long it takes me to get going to do anything at all. I've lost 3lb in my first week. I am happy with that. Very happy. But I think I could have lost more if I'd gotten up off my arse and exercised. On top of that we have what looks to be the winter blues. Even my son with ASD who likes to wake up at midnight and thinks it's time to get up and play is sleeping more than usual. Do you struggle with exercise in the winter? How do you exercise at home? Are you motivated? I need tips!