I think there are clear guidelines here, as there would be in any relationship types (ok, maybe this is a tad more sensitive, yes), and I don't think you have breached any topic that would cause someone discomfort, but you won't know unless you ask them, I guess.
I would imagine the rules would be (and please chime in everyone, this is a top of my head starter list):
- don't out anyone who doesn't want to be outed - so the suggestion of initials and keeping really obvious details out of the picture is a good one
- don't say anything about anyone that you wouldn't feel comfortable saying to their face
Finally, I do think some folks will be more sensitive than others. And as much as that should be respected, their needs / behaviours would not necessarily be generalizable.