It must be something with 13 year olds. Mine is doing the same thing, could they be speaking with each other !?!?!? Maybe it is just the age, also 13, now with a fear of planes, where did that come from, never mentioned it before on our previous 4 trips. It makes me very very sad, I plan the trips for months, down to every detail , have charts, maps, log books, plans, etc. I was very hurt when she mentioned this to me, as other posters have said, the 6 days mine will be missing school will never be remembered again, but the family being together will. I am a nurse and can not take time off in the "traditional "school holidays as that is also traditionally the time when nurses are most needed (ie: any holiday, pick one). I also feel the school puts pressure on them, 'oh you will miss so much". Well, the school can go take a flying leap, my kids do not stay home for any excuse, go to school when they are sniffling or the weather is bad, or when she has her "monthly" problem or any other whim... They are only out for the most 6 days in a year for our family to be together when they can, and we get homework, and we do it, and we make a class presentation with pictures, I know, maybe my DD is annoyed at the work she has to do in Disney, perhaps it would be easier to stay home, well
TOO BAD to my DD..You will come, You will have fun, just as you have done for the past 4 years...Life is precious.. enjoy these things while we can... and feel thankful we can do this, that we don't live in New Orleans and are suffering the work things in life, but to the OP, boy,
do I also feel your pain 
!!!