somebody'd shoot you for a coyote if you was by yourself. No, you stay with me.
He's my...cousin. Just ain't bright. but he can do anything you tell him.
He ain't much of a talker is he?
In this part, George was a good friend to Lennie, because he gives him advice on how to behave at the ranch. George also tells Lennie to come back to that spot if there was trouble. George takes the time to make sure Lennie knows what he's supposed to do, and sticks with him to help him instead of letting him fend for himself.
This example also shows that George was a good friend to Lennie, because he tries to convince the boss to let Lennie stay and help out at the ranch. To try to cover Lennie's mistake in weed, he makes up a story of why they "quit". George also makes up about how he and George are cousins to make the explanation more plausible.
This last example shows that George is a good friend to Lennie because instead of letting Curley kill Lennie out of anger and revenge, George kills him. I think George killed Lennie because he wanted to be the one to do it and end their friendship. This goes back to what killing Candy's dog foreshadows.