wedding

My older sister and I don't get along well and never have. She lives in Atlanta and we don't see each other except for Holidays. We argue all of the time and constantly disagree. I'm getting married in September and she is not one of my bridesmaids.. I have decided this bc she lives to far away to be involved in everything and we're not close! My mom and dad are pissed at me and think it's the worst decision in the world and that I will regret it. What are yalls opinions??