One of the main themes which runs through the books is loneliness.
George and Lennie are an exception to this as they move round together.
Curley's wife is lonely and this is shown through how she begs for attention round the ranch. She throws herself at the men just because she's bored stuck there all day.
Crooks is lonely mainly because he is black and so the other ranch workers are really racist towards him. He has his own room which people tend not to enter. We know he feels lonely from the conversation he has with Lennie (not that Lennie understands).
Candy is lonely and we know this because his only friend really was his dog; when his dog dies he tries to join forces with Lennie and George for their dream!
This is perhaps one of the most obvious themes of the book; when George kills Lennie at the book this kills their dream about the rabbits and there own land. The dreams give the ranch workers hope and this is why Candy was so keen to give all his money and everything he had just to join up with George and Lennie for their wonderful dream. In a way at the end of the book Lennie dies living the dream as George tells him for maybe the millionth time what they hope for when the gun shoots. Another person who has unforfilled dreams and this person could be said to be disillusioned is Curley's wife; she explains to George and Lennie how she was meant to go and become a star but her mum hid the letter. This shows how unhappy she is on the ranch as she always goes on about being in the 'pitchers'.
REMEMBER WHEN STRUCTURING WHAT YOU'RE GOING TO WRITE, START WITH AN EPIGRAPH AND THEN EMBED QUOTES FROM THE BOOK AND THE WRITER INTO THE TEXT. THIS WILL HELP TO ENSURE TO GET IN THE TOP BAND AND THE BEST MARKS POSSIBLE.