I realize that you have long since been on your cruise by now, but I will post this in case anyone else with the same problem might be reading. As an extremely obese woman myself, I was a little nervous about my first cruise. My fiance and his family had invited me to go with them on the Disney Magic. The thought that popped into my mind was "I'm going to be walking around in a bathing suit for a week? Yikes!" But then I thought what the hell, I'm going on a CRUISE!!!
And I can tell you I was definately NOT the only heavy woman there, and I didn't receive any rude comments from anyone. Granted I don't look like a model when I wear a swimsuit, but I was able to find a couple of swimsuits that flattered me better than others. One of them someone actually bought for me last year, but it's a solid black one piece with shorts a few inches above the knee attached to it, so it looks just as if I'm wearing a tank and shorts. The other is one I found at Fashion Bug and it's a swimdress. So for any plus sizes out there worried about swim wear, check stores that speacialize in plus sizes such as Lane Bryant, Avenue, and Fashion Bug.