Jen, you know of course that your posts had nothing whatsoever to do with your SIL's heart attack, right? And her misfortune doesn't change the truth of her difficult relationship with you. Please don't feel bad.
Michele, why do you choose a cruise as your vacation each year, if you find the alcohol and food so troublesome? Wouldn't you enjoy trying something new and different, that might leave you feeling good about yourself instead of guilty? Have you ever gone with DH on one of his China trips, and then toured around? Or gone on a wilderness camping trip, or a literature tour of central europe or an ecotour in the Amazon? Your moniker is "Traveling Michele" so I suspect you may have, but I don't know that about you. Funny to think I've been on this board for long enough to have had you talk about your cruising 3 times now, and always negatively.
You don't drown in the river by falling in, but by failing to get back up.