How does the setting emphasize the themes of loneliness and isolation in 'Of Mice and Men'?

It is set in the 1930's during the Great Depression. It is on a ranch in the Salinas Valley near the Salinas River, just south of Soledad in California.

The novel opens with the major characters, George Milton and Lennie Small, camping for the night beside a pool along the banks of the Salinas River. The following morning, the two hike to a nearby ranch, where they take up residence in the bunkhouse. Steinbeck paints a vivid picture of the sparsely equipped facility and of the hot, dusty ranch land on which George and Lennie work.

To be more specific, all 6 chapters of the story take place in the following 4 places, respectively:

1. Outside of the ranch, clearing by the lake

2. Bunkhouse

3. Barn

4. Crooks' Room