How does the novel's setting create an atmosphere of loneliness in of mice and men?

No one really knows anyone on the ranch.

George and Lennie have no family and are always travelling for work.

Crooks is segregated because of his colour.

Curley's wife is alone because her husband doesn't love her and the men don't like her.

Lennie is mentally different from the rest of the men.

Candy says that most men stay a month and then move on when their work is done.

The book is cyclic too, in which you go each day with the same situation, you work with the people you see everyday but you make no friends. You're only there to work until you're no longer needed.