My advice to you OP is tell your group that you will sleep in order to help them(Less damage people take, the more DPS you can do, the faster the run will be.), if they break your CC after that warning then stop doing it. Just go full heal mode, If they don't want to be efficient then you shouldn't have to go out of your way trying to help them.

Also the suggestions to let a BLM do the sleeping is valid, but most BLM's at 50 don't bother sleeping and instead AOE everything and it's a reasonable thing.