Daisy is not as great as Gatsby thinks she is. First, he has inflated her in his mind to such mythic proportions that no real woman could possibly live up to his expectations. Nick notes this on the afternoon that Daisy and Gatsby are finally reunited after five years:

Almost five years! There must have been moments even that afternoon when Daisy tumbled short of his dreams--not through her own fault, but because of the colossal vitality of his illusion. It had gone beyond her, beyond everything.

Second, even if Gatsby had not built Daisy up in his mind as the symbol of all his desires, she simply was not a person of great character. She was weak. Near the end, after her flirtation with Gatsby, she went back to Tom, despite all his adulteries. As Nick puts it:

the dead dream ... slipped away ... whater intentions, whatever courage she [Daisy] had had, were definitely gone.

At the end of the novel, Daisy lets Gatsby take the blame for running over Mrytle, even though she was the one driving his car.

Finally, she doesn't show up for Gatsby's funeral, even though he arguably laid down his life for her. Nick writes:

They were careless people, Tom and Daisy--they smashed up things and creatures and then retreated back into their money ...

The novel might show Daisy to be unworthy, but it both exalts and critiques the idea of having a dream: in fact, such dreams, for better or for worse, are at the heart of what America is and has always been, Nick Carraway maintains.  

Is Daisy as great as Gatsby thinks she is? What other characters in literature discover their love isn't as great as they previously thought?

Daisy is not the ideal woman as Gatsby imagines her. While he pines after her and wants to rewind time so that he can be with her before she married Tom, the reality is that Daisy is a selfish and careless person. She marries Tom after he gives her an expensive pearl necklace, and, though she admits to once having loved Gatsby, she returns to Tom in the end. While Tom is a brute and Daisy doesn't care much for their daughter (who she hopes will be a "fool"), Tom offers her the upper-crust lineage and lifestyle she wants. She doesn't even attend Gatsby's funeral in the ultimate show of emotional coldness. The reader might pity Daisy for having to make her life with Tom, but she ultimately shows that she doesn't really want any other type of existence.

Tolstoy's Anna Karenina is another tragic figure in literature who finds that her love affair is not what she had imagined. She leaves her husband for a passionate love affair with the dashing Count Vronsky, and she must abandon her young son for her life with Vronsky. In the end, Anna feels that Vronsky cannot satisfy her, and she becomes possessive and self-tormenting and ultimately throws herself under a train in one of the most tragic scenes in literature. Her descent from passion to madness is hard at times for the reader to understand, but it in part...

Is Daisy as great as Gatsby thinks she is? What other characters in literature discover their love isn't as great as they previously thought?