AAAAGGGGHHHHH!!!!!!!!!!!!!

My sister drives me bonkers! Last weekend I had a huge birthday party for my two foster daughters who have birthday's close together. We had over 30 children invited plus some of their biological family (NOT the parents) as well. About Wednesday of that week the weather was forcasting rain so we moved the party from Sat. to Sun. T was so happy and thrilled because she had never had so much as a birthday cake never mind a big pool party, with decorations. She invited a whole bunch of girls from her class. C also had invited a bunch of friends and they were both looking forward to seeing their grandmother, biological brother and Aunt and Uncle. Friday afternoon (after spending all day shopping for birthday party supplies) I am talking on the phone to my sister and reminded her that the girls' party was going to be on Sunday because of the weather. She then proceeds to start yelling at me saying that her daughter's dance recital was on Sunday and that I had no right scheduling the party on that day and I needed to cancel the party outright because as far as she was concerned my niece should be more important to me than my foster children. The thing is, I had NO IDEA that my niece's recital was on that day. My sister had mentioned it at Easter dinner but never gave me the exact date and never mentioned it again. I told my sister 3 weeks in advance about the birthday party and told her Wed. that the party was being moved a day because of the rain and she never said anything about the recital. I have to admit that I got a little too angry with her and said a few not so great words and hung up on her. My sister tends to be a bully (she has alienated almost everyone in her husband's family) and has the attitude of when she says jump we should all ask her how high! The thing is too, that my niece could care less whether I am there or not! She is only 4 and not very close to me. I don't know, I just don't get it!!!
Sorry about venting but I now that someone on the board will understand! Thanks!