My So Called BFF and the Beach House

So check this out. I get my sister-in-law's beach house for the weekend. No charge. It's end of season and she had an opening. I was sooo excited. I fully intended on going by myself to do some soul searching and some R&R. A few weeks went by and I talked it up to my BFF. As time went by I was hanging out with another friend. We got into a deep conversation about life and relationships. Since I was soul searching and she was soul searching I asked her to go with me. It would be a good weekend for two pals to spend sometime together pondering life and love. During the weekend I found out that she never had been away with a girlfriend on a "girls" weekend. She got pregnant early in life and then proceeded to have a family (4 kids) and probably the same number of husbands and/or boyfriends. hahahah We had a great time. We talked alot, ate alot and laughed alot. It was real nice time. My BFF however seemed to be really annoyed, all of which I just didn't get until she informed me that she was hurt that I didn't ask her to go. I was like HUH? She had a wedding to go to and couldn't go. But according to her I was supposed to ask her anyways. Why, so she could tell me NO!!! So we are in a fight now because of it. I am really confused. I thought we were grown ups. She told me she brought it up because she wanted to clear the air and she thought we could share things like that. I was like HUH? It just doesn't make sense to me and she and I have been friends for about 15 years and never had a fight before. One small misunderstanding once but nothing crazy like this. I just am stumped. I don't think I did anything wrong and if she wanted to go she could have hinted to it, or just plain out asked me. She had plenty of opportunities. She wasn't shy about it after the fact. It is like being mad at someone for their good fortune. Now my wonderful weekend has been cheapened by this and it SUCKS! My Ex-BFF has so many things in her life. She spend a week at the beach this summer, she just went on a cruise, and just added on a screen porch to her beautiful home. My other friend lives pay check to pay check. I was really happy to be able to invite someone who was able to enjoy it so much. God does things for a reason. I have no idea what he wants me to do now. I guess I will have to wait and see.