Clearly, Jay Gatsby is a tragic figure; he has aspired to empty dreams. For, just as his life has been lived in pursuit of the false American Dream of material possessions and the love of an illusion of beauty and goodness in Daisy, so, too, is his death false and empty.
It [the "dream"] is significant that Jay Gatsby lies face down with arms stretched out upon his air mattress after his murder. Indeed, the resemblance to a Christ-like figure, the sacrificial victim, cannot be missed as Jay's death saves Daisy from ignominy. That the Buchanans move away and none of the many guests from Gatsby's parties underscores the falseness of his life and the falseness of his friends who abandon him or sacrifice him to perserve their own aristocratic reputation. Only "Owl-Eyes" attends, for he knows and sees everything, saying "Amen to that" after someone murmurs "Blessed are the dead that the rain falls on." Nick has just told him that Daisy sent no message or flowers.
Continuing the tragic motif--Jay Gatsby's father arrives,
his face flushed slightly, his eyes leaking isolated and unpunctual tears. His grief began to be mixed with an awed pride
as he exults in Jay's material possessions, underscoring further the falseness of the era, the symbolic green light leading to money and materialism that Gatsby chased, all his longings and needs that came, tragically, to nothing. Nick's final words are these:
It eluded us, but that's no matter--tomorrow we will run faster, stretch out our arms father...And one fine morning--
So we beat on, boats against the current, borne back ceaselessly into the past.
Gatsby's funeral is the epitome of Fitzgerald's disillusionment with not only the American Dream but also with Old Money Society. Not a single person from Old Money Society (i.e., East Egg) attends the funeral. In fact, only several people stand around Gatsby's unadorned grave--Nick, Gatsby's father--Mr. Gatz, a couple of working class folks (servants and a postman), and the minister. Owl Eyes does show up, and this is significant because he represents an uninvolved spectator god--one who watches the tragedies of humans but does nothing to intervene. The careless wealthy, namely Tom and Daisy, have fled in their cocoon of wealth. Gatsby's "business associates" like Wolfsheim do not attend, and none of the hundreds of partygoers who mooched off of Gatsby's generosity while spreading rumors about him could find the time to come.
The funeral shows that no matter how hard one works to accomplish his or her dreams in America, he won't succeed, and nobody will care--especially those from wealthy America (this is the author's view of the American Dream). Even the weather--rainy and dreary--complements the entirety of Fitzgerald's disillusionment.
I believe that the most significant think about Gatsby's funeral is how essentially no one comes to it. Nick Carraway tries to call a bunch of people, but he cannot get any of them to come.
This shows how empty Gatsby's life was. He was constantly surrounded by people. He had all those parties and everyone always wanted to be around him. But when he died, no one cared except for Nick, his father, and a few servants.
So his funeral just emphasizes how essentially sad Gatsby's life became by the time he was killed.