In Parul Sehgal's talk about jealousy, she brings up a very relevant point on how without envy, literature would cease to exist. She brought up Proust and his obsessive jealousy, Freud and his study of a man and his suspicions of his innocent wife.
We make ourselves feel jealous in order for us to cope with how we feel for another person. We make up stories in order to make us feel better/worse about our envy.
Jealousy can also drive people to commit drastic measures, such as the anecdote that Seghal shared to the audience. People will do what they can in order to make themselves benefit, whether to ease our jealousy or to improve our daily lives.