Death of a Salesman

Death of a Salesman took place in the 1940's, a very different time period that I'm accustomed to reading about. Willy (the father) seemed to have some sort of mental illness that his family didn't take very seriously. He had moments that was out of the ordinary. He often had daydreams inside his original daydream which seemed to occur when he was going on a rant. He often had very negative thought toward his son Biff, despite Biff's efforts to make his father happy. Happy seemed to e the preferred son of Willy, his accomplishments were always praised by his father and everything he did was pleasing to Willy.
While trying to find the "American Dream" the sense of a functional family seems to be lost. Each character has a dream of their own, for example Biff and Happy want to move out to a ranch out west. The death of Willy outs an end to that dream when Happy declares he'd stay in New York for a little while longer. The Death of a Salesman was a very confusing book to me. The time changes and unrealistic things that happened throughout the plot just added to my confusion.