My husband's "little sister" often comes to my house to eat and shop with her mother-in-law.

I heard my husband say that the girl used to go to the same university as my husband, she was 4 years younger than him, and was also the daughter of his mother's friend. The two mothers originally intended to matchmake their children together, the girl also really liked my husband, but my husband didn't pay any attention.

After we got married, my husband's "little sister" often came to my house to eat and shop with my mother-in-law. Many times she deliberately tried to approach my husband, then tried to speak ill of me and destroy my relationship with my mother-in-law.

She came to my house to play, as a guest but naturally treated herself as if she were at home. She was friendly with everyone in my husband's family, but when it was just me and her, she no longer had a gentle and lovable expression but an openly challenging attitude.

I talked to my husband, but he said I was too sensitive and jealous for no reason.