West -> East

• The fact Nick moved from the Mid-west, where there were more conservative moral views but moved to the East (New York), where there is a more slack view on morals. Therefore, the midwest is representing the traditional American values whereas the East is representing the more modern, morally-weak america.
• In terms of the comment, the reason Nick cannot adapt to the Eastern life is because he finds the place to be superficial, as he witnessed when only one of Gatsby's guests (owl eyes) came to hi;s funeral despite thousands enjoying his hospitality at his extravagant parties. Highlighting the theme of the loss of morals and the superficiality of the elite.
• "I see now this has been a story of the West, after all [we] were all Westerners, and perhaps we possessed some deficiency in common which made us subtly unadaptable to Eastern life."