A lot of people on DISBoards (not pointing fingers at anyone on this thread, but just saying in general) seem to view annual Disney trips as a right and necessity. You're going on one trip in a few weeks and that is AWESOME, but it might be time to start putting away money for something else, once you get home.
That said, only you can decide what your priorities are and how to spend your money. If taking your kids on nice trips before they leave home is a priority to you, then that's your decision. There's nothing wrong with that.