help My really skinny sister makes feel like shit!

my older sister is alot skinnier than me and she is always flaunting her body in tight clothes and looks great which is fine Im glad she looks good! but she knows im am struggling to lose weight and asks me multiple times a if she looks fat and where she wants to lose and ten more pounds when she doesnt need. I starting to drain me and make me feel like shit. Ive told her it hurt my feeling and to not ask me but she doesnt it anyway.HOW DO I MAKE HER STOP??