What are the motifs in Talley's Folly by Lanford Wilson?

Family is a recurring idea. More than anything else, Matt and Sally are longing for a family, although it will be a new kind of family. Matt's parents and sister were tortured and killed in Europe for political reasons. He escaped to America with the help of an uncle, but does not seem to have a relationship with that uncle now. He is alone. Ironically, Sally, who shares a house with three generations of Talleys, is also alone. She draws no comfort from her family, who have rejected her because of her political beliefs and because she has let them all down by not marrying Harley Campbell.