The Land in Winter by Andrew Miller

December 1962, the West Country.

Local doctor Eric Parry, mulling secrets, sets out on his rounds, while his pregnant wife sleeps on in the warmth of their cottage. Across the field, funny, troubled Rita Simmons is also asleep, her head full of images of a past life her husband prefers to ignore. He's been up for hours, tending to the needs of the small dairy farm where he hoped to create a new version of himself, a project that's already faltering.

But when the ordinary cold of an English December gives way to violent blizzards, the two couples find their lives beginning to unravel. Where do you hide when you can't leave home? And where, in a frozen world, can you run to?