If you have ever made vacation plans and had to cancel them completely, what was the reason and the intended destination?

Yes.  A friend and I had booked a two-week trip that included a cruise to Alaska.  Two weeks before the trip, I broke my ankle and was in a hard cast from toes to knee.  Fortunately, we had taken out trip insurance and were able to book the last such trip two months later.  

We planned our wedding trip to Cedar Point, in Ohio. For some reason, the spouse decided we should not go.

I've made a lot of plans I've had to cancel completely!