In Of Mice and Men who is responsible for Lennie's death? Why? (You can't say George because he was the one who shot him)

There are many ways that this can be interpreted. One answer can be Curly's wife. She was bored with life there and liked talking to men so if she hadn't been flirtatious and promiscuous, Lennie wouldn't have ended in the situation. On other hand, you can say that it was Curly's fault since she wouldn't have behaved so if he paid more attention to her and was a better husband.