If a random guest came to me on my wedding day and said "I don't want you to post any photos of this event online because one of my friends just lost their spouse and I don't want them to see me at a wedding at this time", my response would (rightly) be - I'm sorry for their loss but that isn't going to stop me from celebrating my day in whatever way I see fit. Yes I obviously wouldn't go out of my way to call and tell the grieving person about how much fun I had, but people understand that life goes on, and the entire world doesn't have to be sanitized to meet individual people's preferences.