“She never loved you, do you hear?” he cried. “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!”
This is how Gatsby rationalized Daisy marrying Tom to himself, so that he could keep the dream of reuniting with Daisy alive. He assumes that the only reason she could ever marry anyone except him was money, and now that he had money she would pretend that the last 5 years never happened. He never asked Daisy about any of this, he just assumed it had to be true.
To help improve the meaning of these lyrics, visit “The Great Gatsby (Chapter VII)” by F. Scott Fitzgerald and leave a comment on the lyrics box