I too don't eat any meat, dairy, or eggs. I have been on RCCL, Celebrity, Carnival, and Costa. They have vegetarian menu selections, but frequently they use cheese or dairy in the menu items. The best solution is (to have your TA) to notify the cruise line ahead of time. Then before or during the first evening notify your waitstaff and head waiter of your desires. The Head waiter can and should bring you the next day's menu and you can then modify what is available to suit you, or he can suggest, or you can suggest something else. Typically it might be good to have some idea what you would like, I ususaly didn't....I've learned now to come prepared with suggestions. You can also ask for the fresh veggies that are the side dishes on the other menus and this shouldn't be a problem either. Buffets you can see what is there, or you can negotiate for a breakfast or lunch also with the headwaiter.