This reminded me rather a lot of Graham Joyce's The Silent Land, which I just read recently. It contains a lot of the same themes and motifs; solitude, a transitory(?) afterlife, etc, using some of the same symbolism (cold, snow, finite and dreamlike realities).
This book is much more explicitly apocalyptic: a virulent pandemic sweeps the earth; one woman in solitude in the Antarctic struggles to survive and contact others. Meanwhile, all the people she ever knew or remembers exist in an oddly mundane afterlife.
I enjoyed the writing style and the concept, but I wished that more had been done with it. It's more about mood than plot, and the ending felt a little flat.