Irony of Curley's Wife's Statement

In of Mice and Men by John Steinbeck there is irony in the statement made by Curley's wife. “They left all the weak ones here” (77). Curley went to town with George, Slim and several other men. Meanwhile Candy, Lennie and Crooks stayed on the ranch. The ironic part of the statement is that Curley's wife knew that Lennie beat up Curley in the fight scene, but she still called him weak. I think that Curley's wife was trying to get in their heads and tell the men that they are worthless. Also I think that she meant Lennie is weak because he is weak minded, Candy is old and had lost a hand, and Crooks is black. I am not sure why Curley's wife came into the barn in the first place but she definitely was not looking for friendship. I hope to find out!