There Is a lot of loneliness on the novel Mice and Men, One example could be Crooks, nobody talk to him because he's "black" and also another good example could be Candy when Carlson killed his dog he felt alone and lonely and Also Curly's Wife, Curly didn't want her talking to everybody and she was lonely P.S. I love this book and I'm not 100% sure It's Carlson who killed Candy's dog