Opulent jazz life
This couple is a stylish duo who are young and hip enough to find their way into cool environments where the jazz age is in full "swing," so to speak. That is an imagery that speaks for itself, as any fans of Fitzgerald's could attest, but in this book, the dual imagery of Gatsby comes back with vicious intent. Yes, the imagery in concrete language seems opulent and gorgeous, full of joie de vive, but actually, the imagery has an abstract quality that Damns it so to speak; it is expensive and in order to keep up with the Joneses, one must use credit for appearances alone.
Recompense and karma
The fateful tone of this novel comes from the use of recompense imagery. This is natural because the novel is set in the birthplace of the US credit system which allowed people to spend more money that they could reasonably afford for the first time. However, when it comes time to pay the bill, credit systems leave poor people feeling self-damned and doomed to extreme financial woes. This is primarily shown through the crises of Anthony's marriage with his wife. As they spend, they betray themselves more and more and their dysfunction increases. Without financial control, their marriage is doomed.
Alcoholism and addiction
The devil is in the details when it comes to alcohol. What is wrong with Anthony's drinking? Well, there is much to be said; the imagery describes an alcoholic without a mental framework for understanding the warped nature of his own perception. His drinking is similar enough aesthetically to the drinking of his friends and family (who are also drinking far too much) that he does not have to admit where his drinking differs from theirs. Gloria knows exactly what is wrong with his drinking. In public, it seems social, but in private, the drinking only escalates so that he is clearly seen as an alcoholic who uses drinking as an escape from the emotional burdens of his daily life. The imagery fades to black as he blacks out day after day.
Death and doom
Well, the beauty of the novel is pretty obvious, so where are the Damned? Anthony's doom provides imagery for damnation. In light of his personal hell, what is the value of his true love? Nothing. In light of his abstract, invisible suffering, so complicated and emotionally deep that he cannot articulate its nature, what is the value of money or style or appearances? He starts the novel caring so much, but slowly, his damnation becomes evident; he is being doomed to apathy and anhedonia. When his life no longer matters to him emotionally, an ennui sets in that leads the reader to suspect he will kill himself, either by alcoholism or suicide.