As friends, Lennie Small and George Milton are misfits, both physically and mentally; and, yet, each is dependent upon the other. However, this dependence creates a certain anxiety.
Physically larger and stronger than George, Lennie's strength does less to defend George than to cause him worry. As they enter the clearing in Chapter I, Lennie appears bear-like, dragging his feet behind him. He hides a mouse that he has been petting, but after George discovers it, he tosses the rodent away; nevertheless, Lennie tries to find another. Always Lennie is too strong, crushing anything he captures. As they sit around the fire, George recalls the girl from Weed and expresses a wish that he could travel alone because
"I could get along so easy and so nice if I didn't have you on my tail. I could live so easy and maybe have a girl."
As he prepares the meal for them, Lennie asks for ketchup that George does not have. When George becomes angry, Lennie says that he will go away and live in a cave or somewhere. But, of course Lennie cannot live by himself, so George has to appease him.
Of course, George is always worried that Lennie will overpower the other bindle-stiffs, so he cautions the big man about staying out of trouble. When Curley's wife stands seductively in the doorway, George takes him by the ear exhorting him, "...She's a rattrap if I ever seen one." But, Lennie protests, saying he has not done anything, and he wants to leave, "I don' like this place, George. This ain't no good place."
When he pets the puppy given him by Slim, he accidentally kills it. Then, he is anxious about what George will say, "I done a bad thing....George ain't gonna let me tend no rabbits now." Later, when he inadvertently chokes Curley's wife, Lennie becomes extremely anxious about George's response. knowing his action is a repeat of what had happened in Weed.
Compellled to care for Lennie out of a sense of obligation because the man's aunt has died, George resents Lennie at times; however, even in his irritations at Lennie's repeatedly asking for a repetition of the dream of owning a farm of their own, George begins to believe in this dream. However, his mistrust of others and anxieties prevent him from letting Lennie really enjoy himself. Instead, he feels the need to scold the big man. When he talks with Slim about Lennie, George explains their friendship in somewhat negative terms which hides the real comaraderie they share,
"'Course Lennie's a god damn nuisance most of the time...But you get used to goin' around with a guy an' you can't get rid of him."
Further, George mentions how he used to tease Lennie until the man nearly drowned. Then, he stopped.
Thus, in their relationship George and Lennie both have feelings of anxiety and negativity toward each other either from disparagement or fear. This negativity often arises from their alienation and loneliness, which ironically, unites them as well by the hope that their dream of a farm affords them.