Nick Carraway is one of the enigmas of the novel, The Great Gatsby. He is the narrator of the story, but reveals little about himself. At the beginning, he is honest. He grew up in Chicago, graduated from Yale, enjoys literature, and works in the bond business in New York. Nick is not rich; however, he has connections to the wealthy and socially elite, like Daisy and Tom.
By the end of the novel, he has been tarnished by Gatsby's world and has paid a dear price for it. He has sacrificed his honesty and high standards by hobnobbing with Gatsy, Daisy, and Tom. After his fling with Jordan, she accuses him of losing his honesty.
Nick is worried about being alone, and at the end of the novel, that is exactly what he is--alone. One of his worst fears has been realized. Nick vows West Egg and New York are no place for him, and he vows to leave.