I live in Chicago. Since the beginning of October, I have barely made it out the door of my apartment, except to go to work. GROCREY SHOPPING is an accomplishment for me! I don't want to do anything at all and I know if it were warmer I would be outside walking around constantly. I hole myself up in my bedroom watching boring movies and tv shows I've seen a thousand times on Netflix. I have a very warm winter coat, but as soon as that cold air touches my skin anywhere I'm instantly in a terrible mood all day. It's gotten to the point where moving to California seems extremely appealing and not just in the winter (I was in L.A. in August and I didn't want to leave).
You may have what is known as agoraphobia but that is if you're afraid of leaving....but I think for you the key is finding how to make yourself more comfortable to venture out such as a warm drink, etc....focus on what is going right, what you are excited about!