Five years .
Daisy meets Gatsby when he is training to be an officer in Louisville. They later meet again through Nick Caraway.
It had been 5 years since Daisy and Gatsby first united.
Gatsby found out that Daisy had married Tom while he was at Oxford when he returned to the United States and learned about it through mutual acquaintances who shared the news with him. He had been in love with Daisy since before she married Tom, and was devastated to discover that she had married someone else in his absence.
Gatsby believes that by impressing Daisy with his extravagant parties, he can win back her love and erase the five years they have been apart. He hopes that through his lavish gatherings, Daisy will see his wealth and status, and he can recreate the romantic relationship they shared before.
Tom cheats on Daisy with Myrtle, but he treats Myrtle poorly.
Tom realizes his wife, Daisy, has been having an affair with Gatsby when he sees Gatsby's cufflinks in Daisy's possession and notices the strong connection between them during a confrontation at the Plaza Hotel. He also picks up on their subtle gestures and glances that reveal their secret relationship.
Gatsby's vigilant watch for Tom's abuse of Daisy is ironic because he himself has been pursuing Daisy despite her marriage to Tom. By being overly concerned about Daisy's well-being while also engaging in an affair with her, Gatsby's actions reveal a contradiction in his character and his moral compass.
Nick says that Gatsby's act of standing on the dock staring off is like he is "watching over nothing." In fact, Gatsby is gazing in the lighted direction of the object of his affection, Daisy, the woman who has been so idealized in Gatsby's head that the reality of her persona cannot possibly compete with the preconceived notions that Gatsby had developed. She is represented as beautiful and charming, but in the end Gatsby's expectations were still let down. The mental picture of Daisy meant everything to Gatsby, but the real Daisy meant nothing.
Gatsby believes he has been in love with Daisy for five years, so in his mind, he has been seeing her all along despite their physical separation. He holds an idealized image of Daisy in his mind and their past relationship, which makes him feel as though he has never stopped seeing her.
Before leaving for the war, Gatsby leads Daisy to believe that he was of the same social status as she. He allows her to think he is rich and would be able to support her and her lavish lifestyle.
Daisy and Tom invite Nick to dinner at their house because aside from Tom and Nick going to college together, Daisy is Nick's cousin twice removed. There may also be a hint that Daisy wanted Nick to meet Jordan Baker and maybe go out with her, though this is not fully known
Gatsby's Romantic pusuit for Daisy Buchanan is ruined when he kisses her. Gatsby attempts to transcend materialism and superficiality of the 1940's American jazz age with a Romantic love, transcendent of reality and the social deterioration of values. In turn, when Gatsby kisses Daisy, their love becomes a reality and therefore loses its transcendant qualities. Once their love becomes part of reality, it is temporal and must meet mortality and loses its timeless characteristics. Therefore when kissing Daisy, Gatsby is giving up the transcendent qualities of a Romantic love