My sister has decided to involve jump into the plans my fiance and I have made by getting married. The problem with her is that she has literally known her soon to be fiance for a month and wasn't planning on getting married (actually they weren't even dating exclusively) until after I had told her that my boyfriend of almost a year was going to ask for our father's blessing while we were home for the holidays. From my perspective every time I do something good or notable my sister has to make the whole situation about herself or one-up me and take all the attention however she apologized and was trying to be better up until now. I'm not saying I want all the attention but getting married is important and I was looking forward to just sharing that time up to the wedding with my fiance and no one else.
She hasn't officially gotten engaged yet but she and her boy have chosen to get married a month and a half before the date my fiance and I chose. We have about 3/4th the same guest list as my sister and I have a huge extended family so it is going to put a financial and time strain on those of them who choose to attend. The other issue I have is that my family is heavily religious and I am not. My wedding will be traditional but not religiously affiliated (I'm not getting married in a church or religious temple) which will make some of my relative less likely to attend already as they are very religious as well. Of those still who might have come to mine, despite it not being religiously affiliated, they are more likely to attend my sister's wedding now as she is planning on making it a religious spectacle and since it is so close to mine they cannot financially afford to attend both if they even wanted to attend mine after my sister's.
My fiance and I tried to plan our wedding in a bit in advance and I gave my parents notice about 6 months before he asked for my father blessing that we were talking about getting married so that they could save as my parents are not rich people. I feel very disrespected by my sister and upset for my parents. The money they had for my wedding and their savings to make needed repairs to their house is now being split and given to my sister.
Now with my sister jumping in the middle of everything my fiance and I do not feel like being apart of their wedding and I have also banned my sister from attending mine. We are not sure what else to do as my sister and her boy do not care that they are making things difficult on my parents or being disrespectful to me and my fiance. Siblings should not have their weddings close together at all. I have tried to explain things to her but she won't listen.
My parents are trying to be supportive of her despite everything and do not see my concerns as valid or simply dismiss them while trying to support her.
How do I deal with this beyond what I already have done? I do not want my sister to keep walking all over me or my parents but I didn't want to exclude her from my wedding to make that point. I feel like that's my only option though.
