Final answer:
Gatsby tells Nick about his romantic past with Daisy, his deep love for her, and his longing to rekindle their relationship despite her marriage to Tom Buchanan.
Step-by-step explanation:
In F. Scott Fitzgerald's novel The Great Gatsby, Gatsby reveals to Nick that he and Daisy had a romantic past before he went off to war and she married Tom Buchanan. Gatsby fell in love with Daisy, and the love he had for her was deep and stirring. Despite their separation and Daisy's marriage, Gatsby held onto the hope of rekindling their relationship, going as far as buying a mansion near hers and throwing lavish parties with the hope that she might attend. Gatsby's past with Daisy is central to his character and to the story's themes of longing, the transformative power of love, and the disillusionment of the American Dream.