Is it all in my head? Or could I be right?

I live in a different state than my father, but I visit him and his new family twice a year. I feel excluded there because one of my sisters is very attached to my step sister who used to live there. I have asked if I could have a nickname from just my sisters before and the parents said no, but my step sister does get to. I want to practice driving with my dad and he won't let me, but my step sister drove with him while she was learning. He left when I was two and remarried nine years ago. Do you think my real dad loves/likes my step sister more? I have tried my whole life to make him notice me, but he isn't satisified. I try to do activities he enjoys and I get almost perfect grades, but he always wants more. He treats my brother terribly to the extent of not having him visit when I do.