Heather Willette has a good life in Concord, Massachusetts -- complete with a husband who runs his own business and a son to take up his mantle one day. However, now that her marriage has fizzled out and Ross, her only child, is graduating from college and getting serious with his girlfriend, Heather wonders if that life is the one she really wants. Ready to seek out her own happiness and discover herself again, Heather decides to leave her husband and rent a cottage on Nantucket. And her plan is going perfectly -- until Ross announces he's moving to Nantucket to work at his girlfriend's family's construction business instead of going back home to work with his own father, like he'd promised. Worst of all for Heather, this means having to get along with the girlfriend.