I feel most comfortable sitting in front of the TV with my family, with one of the cats on my lap, and the fireplace burning. Unfortunately, I'm now living on the opposite side of the world to those things
Usually I'd say the solitude of my apartment is where I'm most comfortable, but lately coming home to that emptiness has left me feeling fairly depressed. Instead I'd say I feel most content when out walking somewhere in nature, such as a footpath around a lake or alongside a river. Something about being under the trees or near water is very calming to me, enough that I don't mind sharing the space with other people like I would anywhere else.