Our answer: Not to buy. No way, no how would I buy cruise insurance. I'm going, no matter what and nothing's stopping me!! I don't care if I'm sick (where else would you be better taken care of) or someone in my family is sick (I know they'd rather have me on the cruise). I cannot think of one reason that would stop me from going on the cruise.
IF, by chance, some catastrophe did happen, I would consider it "luck of the draw". I'd rather have that extra insurance money to put a deposit on my next cruise than on something I MIGHT use like insurance. Call me reckless or a gambler, but that's what works for me. I only book with big reputable companies, well-known cruise lines and we are all young, healthy and our immediate family is too. It all depends on your risks - if they are too great, then buy insurance. If not, use the money to put down a deposit on your next cruise!