The truth is that not all beaches are so pristine and picturesque. Most are littered. The water is polluted and the scenery is dull. There is also the fact that even if the beach wasn’t crowded when you got there, once everyone on the ship gets off, it will be. With so many chances to bond, there is no way you will not make a friend.
They practically force you to get to know one another through confinement. Every stop, every meal, every activity, and almost every other moment will be spent with this same group so it is best you get used to that idea from the start. There is no escaping it so hope for the best.