Explain the relationship between George and Lennie in Of Mice and Men by John Steinbeck?

The relationship between George and Lennie is a complex one. 

First, George is like a father to Lennie.  George takes care of Lennie in various ways.  For instance, George makes Lennie throw away dead mice that might make him sick.  He also reprimands him when he drinks too much stagnant water, which might make him sick.  Also like a father, George takes pride in Lennie when Slim says that Lennie is a great worker. 

Second,...

The relationship between George and Lennie is a complex one. 

First, George is like a father to Lennie.  George takes care of Lennie in various ways.  For instance, George makes Lennie throw away dead mice that might make him sick.  He also reprimands him when he drinks too much stagnant water, which might make him sick.  Also like a father, George takes pride in Lennie when Slim says that Lennie is a great worker. 

Second, Lennie looks up to George and trusts him.  He probably does not see him as a father figure, but certainly as an older brother.  He knows that George will take care of him. 

Third, George and Lennie are friends.  This is the most profound point in the story.  One of the main points of the story is that loneliness reign over and pervades the lives of everyone.  Right from the beginning this note is struck. George says:

“Guys like us, that work on ranches, are the loneliest guys in the world. They got no fambly.

George continues:

“With us it ain’t like that. We got a future. We got somebody to talk to that gives a damn about us.

Even Lennie chimes in:

“But not us! An’ why? Because . . . . because I got you to look after me, and you got me to look after you, and that’s why.” He laughed delightedly. “Go on now, George!”

In conclusion, George and Lennie care for each other.  This is the only bright spot in the whole story.  They are friends, true friends.