Why did the wife kill in the fresh movie?

The reason why the wife wants to kill someone in the new movie is that the murderer said he was jealous, or that he was really jealous of Mills. According to relevant public information, this situation was caused by an attack on him and his wife, who died in the attack. Leonard's last memory was his wife's death. He can't live any longer. His only thought is to find the killer of his wife.