From a 2-time winner of the Governor General's Literary Award, an intense novel of loss, memory and the limitless nature of family love.     Hal Wiens, a retired professor, is mourning the sudden death of his loving wife, Yo. To get through each day, he relies on the bare comfort of routine and regular phone calls to his children Dennis and Miriam, who live in distant cities with their families. One snowy April morning, while drinking coffee with his Dené friend Owl in south-