Bridal party horror stories?

Well it isn't really a BP story. It is a SISTER story. She will be my MOH and my only attendant. I'm getting married in March in FL (we live in NY). We have known this since this March, so she has a year's notice. I keep trying to talk plans with her and she will not commit to coming. Says it's a lot of time to take off to drive to FL. I offered to pay for her plane ticket. Her boyfriend won't fly. She is making me nuts. I don't know how long to wait before finding another MOH. It will suck if she isn't there. She is my only sibling.

I was in a BP of 7. 2 were out of state, two were the brides older sister in laws, one was the brides niece, and the last one is my friend. The bridal shower fell on the 4 of us who where in the state and of age, and her SIL's insisted on throwing it at a country club to the tune of $400 a piece. When the Bachelorette party came around the 2 SIL's refused to contribute a dime and when my friend and I confronted them about it, they called the brides FH and claimed we were trying to scam them out of $$$. My friend and I had to pay for the whole thing. (Another $300 each). Add the $300 gift, and the $200 dress and all other expenses, total to be in that wedding, $2000.

My sister was my original MOH. She had a fit about something non-wedding related, then said she and her daughter (who is also my god-daughter) will be busy the day of the wedding and probably cannot make it. She is a huge drama queen, my mom warned me not to ask her back into the bridal party but I only have on sister and I have 'sucker' written on my forehead so she is a BM for now; however I am thinking she might drop out once we have to go get the dresses because of expenses.

We also are getting married in Fl and are from NY. I asked my sister to be my MOH because she cried when my other sister didn't ask her. I kept asking her when she wanted to go dress shopping, and she kept saying she was busy.Apparently she never planned on going to my wedding, because I didn't give her a plus one. I didn't know that she was even with someone...she has never had a relationship, and doesn't have any close friends really either, so I didn't think of it. Well yeah she has been with this person for like 2 months and is getting married next month, and isn't coming to my wedding because I(as well as everyone else) didn't know.