The climax of 'The Great Gatsby' starts when Tom finds out about the affair between his wife, Daisy, and Gatsby.
Despite his arrogant, masculine pride, Tom is clearly moved by what he has discovered about Daisy and Gatsby. As they move from the Wilson’s garage to the suite at the Plaza, it is clear that he cannot endure their obvious love. Tom even accuses Gatsby of lying about being an Oxford-educated man. Though Gatsby clarifies that he was at Oxford, but only for few months. It doesn't makes Tom satisfied. In fact, Tom doesn't seems to be bothered about the fact that Gatsby is 'Mr. Nobody from Nowhere.'
Fitzgerald develops Tom's character from a two dimensional stereotype to a tortured man who exhibits love, tenderness and devotion. Tom calls out the affair in front of Daisy and Gatsby. Meanwhile Daisy doesn't say her line about loving Gatsby. Gatsby wanted Daisy to say she never loved Tom but she could not come to do it. So, Gatsby tells Tom that 'She only married you because I was poor and she was tired of waiting for me. It was a terrible mistake, but in her heart she never loved any one except me!' (Gatsby, 130). This breaks down Daisy and she admits that she did love Tom at one point but not anymore. She clearly loves Gatsby but cannot bring herself to admit that she never loved Tom.
Daisy cannot live up to Gatsby’s expectations, he wants too much from her - no one can erase their past or deny their feelings. This is something we have suspected throughout the novel. Fitzgerald included this confrontation of climax as a way of showing Daisy as a middle ground type. She couldn't commit to one because she was torn which suggests balance. At the end, Daisy's ultimate choice comes as a surprise for Gatsby. Gatsby loses her by asking for the impossible.