It isn't as if my family comes from a tradition of keeping secrets from everyone about everything - generally I think they have fairly normal standards that way. My friend group is mostly the same. I am definitely the crazy outlier sitting comfortably 3 standard deviations from the norm in this regard. Even now with me talking about relatively openly about sex and relationships here I am still holding an awful lot back that I would very happily slap up on the internet if it wouldn't upset those close to me. I often think about embracing radical honesty but I couldn't do that without renegotiating an awful lot of my relationships.
Deciding what to post and what to keep secret is a tricky thing. I don't make those decisions in a vacuum because I want to be sure that if I am sharing someone else's secrets that they are on board with that decision. However, I won't allow anyone veto power over talking about my own secrets. I can and do show restraint sometimes when asked though. For example, I waited more than a year to make the first post talking about my own polyamory even though I was itching to spew it forth immediately.
The thing that doesn't add up in my mind is why so many people seem to place privacy as on an entirely different plane of importance than disclosure. There seems to be an assumption out there that if anybody doesn't want a thing being said then it shouldn't be said. I don't buy into that view at all. Rather I strongly prefer the assumption that all things are fair game instead; silence should exist but it should be exception, not the default. That doesn't mean you have an obligation to divulge your own secrets, just that you won't dump on me because I choose to talk about my own stuff.
This extends to the things I want to hear as well as the things I want to say. Other people often say "Ewwwww, TMI!" when somebody else starts talking about their sex life even when it is cloaked in metaphor and indirect references. My reaction is the total opposite - I just want more details! This stark difference is especially obvious when other people express a desperate desire to not know anything about their family members' sex lives as though somehow it would be better if everyone related to them was asexual. In my own head "So this is the new thing I am knitting" and "So X and I were bangin' on the kitchen table and this hilarious thing happened" are equally appropriate dinner conversation for family gatherings. Not that I am more curious about my family's sex lives than my friends', it is just that I see them as equally interesting while the rest of the world seems to see one as utterly taboo and the other as merely a bit risque.
These preferences do not blind me to the obvious; I am able to easily determine what the world thinks is appropriate. I just disagree with the standards I see to such an extent that I can hardly fathom how we ended up the way we are and I can't be happy hammering myself into the box that other people seem to inhabit quite comfortably. Secrets sit inside me and fester, burning away like terrible heartburn that has but one cure - setting the secret free into the world.