I was going to continue with the story of why I have my issues with my sister, but I have decided not to. It's just turned into a big ol' pity party, and that's not my style. Lack of sleep and stress over Xander's issues has made me a bit crazy and I blew things out of proportion. Angel is entitled to her own decisions. I will be there for my nieces if and when they need me.
I will carry on with Xander's party with those who choose to come and I won't fault those who choose not to. I can't say at this point that I definitely won't go to her wedding, but I will say that a lot of healing will have to happen for that to take place.
I can't have regrets for the choices I make. They may sometimes feel like mistakes, but I wouldn't be who I am without them... and I like who I am. Thank you to everyone who offered advice and insight. I truly appreciated it. Hug your loved ones tonight because you never know what tomorrow holds.