My cousin!Help me!?

I don't understand my cousin! Almost everytime i like something she copies me! I know it may sound childish but its really buggin me!She's 13 im 14 And im thinner than her, when we travelled together with our families at lunch time she looked at my food for like 5 seconds!does that mean she wants to be thin like me or perhaps thiner?I love spinach so my grandma made some, and then she ate and she looked at me!Also I always ordered pineapple juice and she thought my favorite juice was apple so she told my mom to get her some pineapple J but she didnt drink it until I did! And please read more>Also i love cinnamon crepe and she knows that and her sister said she ordered it last year after i did ofcourse and im sure that if we went to a crepe restaurant she will order itDoes that mean she wants to make me angry or is she jealous or what exactly? And she's mean 70% of the time and makes a big deal out of everythingmy plan is to be friends with her and talk to her and ask her why!Help!idea?