"If it wasn't for the mist we could see your home across the bay," said Gatsby. "You always have a green light that burns all night at the end of your dock."
Daisy put her arm through his abruptly, but he seemed absorbed in what he had just said. Possibly it had occurred to him that the colossal significance of that light had now vanished forever. Compared to the great distance that had separated him from Daisy it had seemed very near to her, almost touching her. It had seemed as close as a star to the moon. Now it was again a green light on a dock. His count of enchanted objects had diminished by one.

.................................................

"I wouldn't ask too much of her," I ventured. "You can't repeat the past."
"Can't repeat the past?" he cried incredulously. "Why of course you can!"
He looked around him wildly, as if the past were lurking here in the shadow of his house, just out of reach of his hand.
"I'm going to fix everything just the way it was before," he said, nodding determinedly. "She'll see."
He talked a lot about the past, and I gathered that he wanted to recover something, some idea of himself perhaps, that had gone into loving Daisy. His life had been confused and disordered since then, but if he could once return to a certain starting place and go over it all slowly, he could find out what that thing was...

These excerpts come from F. Scott Fitzgerald's The Great Gatsby. As you can see from the quotes the main character Gatsby is in love with a girl he once dated years ago. His life is consumed by the idea of her loving him once again. I understand Gatsby's grief but I also feel sorry for him because of the extent to which he has taken his infatuation. On that note I will leave you part of the ending, when Gatsby realizes Daisy isn't going to be his.

No telephone message arrived, but the butler went without his sleep and waited for it until four o'clock--until long after there was anyone to give it to if it came. I have an idea that Gatsby himself didn't believe it would come, perhaps he no longer cared. If that was true he must have felt that he had lost the old warm world, paid a high price for living too long with a single dream. He must have looked up at an unfamiliar sky through frightening leaves and shivered as he found what a grotesque thing a rose is and how raw the sunlight was upon the scarcely created grass. A new world, material without being real, where poor ghosts, breathing dreams like air, drifted fortuitously about..