There is no true resolution to the alienation of the men within the setting of the Great Depression; the only resolution is that of the narrative: Lennie's death translates as the death of the dream for all who have entertained hopes of owning a piece of land on which they can raise chickens and rabbits and such. As he looks at Curley's wife, the temptress who has caused the fall of the innocent Lennie, Candy knows that nothing will come of his hopes,and he must persevere in living from day to day, anxious that he will be let go.
"You G---damn tramp.... You done it di'n't you? I s'pose you're glad. Ever'body knowed you'd mess things up. You wasn't no good. You ain't no good now, you lousy tart.....I could of hoed in the garden and washed dishes for them guys."
George, too, has lost the dream as well as his companion Lennie; now he is alone in an uncaring world. But, Slim--with the "God-like eyes"--does offer some fraternal comfort, "Come on, George. Me an' you'll go in an' get a drink." Further, he tells George, "You hadda, George. I swear you hadda. Come on with me." Although the dream dies with Lennie, fellowship begins for George and Slim, thereby offering them some hope for meaning.
John Steinbeck called "Of Mice and Men" a "playable novel." He wrote it with the intention of turning it immediately into a stage play to be produced in New York in 1937, the same year the book came out. The novelette is full of dialogue and very light on prose exposition, making it easy to adapt to a script for a play. Because a stage play could not run for more than about an hour and a half, the novelette had to be short. But the story, dealing with crews of farm workers and teams of horses, seemed to call for a panoramic treatment like Steinbeck's The Grapes of Wrath and East of Eden. He decided to bring the novelette to an abrupt conclusion with what editors call a "shotgun ending." One of the main characters would kill the other main character, and that would end their motivation to acquire their own farm, effectively ending the story. Steinbeck had to invent reasons why George felt he had to kill Lennie as he did. Lennie was becoming a menace to society and too much of a burden for George. The book was a big success. The play was a big success in New York. So Steinbeck must have been right. The resolution comes when George pulls the trigger of the stolen Luger.
The resolution of the story is Lennie's death. Although it's kind of sad, Lennie was killed by George after one last talk about their dream farm. They said the farm would have chickens, a garden, and rabbits which Lennie could feed. Lennie's death symbolized the death of both of their dreams and resolved the story. the story kind of goes full circle because it starts off talking about the dream and ends the same way (that's so sad).