A dead , departed mother haunts '' Heart Shaped Rock '' in the form of heart-shaped rocks she 'd made into a kind of cairn outside her Montana ranch house , as she prevails in the memory of her aged husband , now hospitalized in Montana and visited daily by his daughter , Jilly , a hard-drinking , sexually promiscuous divorcee who accompanies her father on -LRB- hallucinated -RRB- drives on Highway 90 between Missoula and Butte .