Why do my cousins hate me?

Ever since I was young my cousins hated me. They would be rude to me for no reason. My mom and my aunt had to tell them to stop being mean to me. Now that I’m 16 one of them still kind of pick on me, she ignores me, her birthday gifts don’t feel genuine. She literally didn’t want me at her baby shower and my mom insisted I go even tho I wasn’t on the list. She doesn’t want me in her wedding either. Today at her law school party I wanted the last ice cream and I called first dibs and she gave it to my aunt. Her mother said be nice and she rolled her eyes. I went to her son’s bday party and her mom asked her to sweep the floor and she got mad at me. Atp I’m so done trying.
Why do my cousins hate me?
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