One of you can fly to Colorado first and buy a bunch of special candy, then re-package it as non-special candy before you go on the trip. It's not the same as smoking, but she definitely won't get in any trouble popping gummy bears on the cruise!
They will sell e-cigs in Colorado too, which would also work great on the cruise, but I'm less certain about flying home with them because I believe they are clearly labeled.
Have fun!