I REALLY don't want to invite my sister to my wedding, and there are several reasons why.
The most recent reason is she bailed on my engagement party because of "unresolved family issues with several members of the family" and she doesn't want to ruin my special night because she "has a mouth and can't keep it shut." That first part is complete BS. Really, she is just a narcissist and a pathological liar. She's raising my niece to be the same way. My niece was going to babysit my nephew so my sister could come to the party. After I found out my sister wasn't coming I invited my niece. Not because I wanted her there, but because she is 15 and doesn't get to do stuff like this (nice dinner party at a hotel). When I invited her I got "No thanks, but thank you for offering. Weddings aren't my thing!" She's too good for important things in my life, but the first time I saw her in a few months the first words out of her mouth were, "Have you seen my report card?"