Not at all. You don't have to go into the ocean if you don't want to. Even if you do, they provide life-jackets and there's a line you can hold on to. But again, there's no need to jump off the boat. When you stop for lunch at Isla Mujeres, there's a beach there and the waters are pretty shallow (I'd recommend bringing swim shoes as the shore is rocky)
I woud ask the captain if there are any life preservers on board which I'm sure he's required to have...Other than that I heard they make a stop or two but its probably on shore.
I cant swim very good sober so im guessing drunk would not work out well for me and been on 6 boobs cruises,,,
