Final answer:
Nick sometimes has a haunting feeling of loneliness and a deep desire to connect with others, reflecting the sense of isolation and lack of meaningful connections in American city life at the time.
Step-by-step explanation:
Nick sometimes has a haunting feeling of loneliness and a deep desire to connect with others. In his description of his feelings and the indication that others feel this way, it suggests that the city life in American society at the time is characterized by a sense of isolation and a lack of meaningful connections.