private identities

I keep coming across that fab quote about being kind to people because we have no idea what they are currently battling.

When doing my diversity work, we used to explore what we called private or hidden identities. Lots of us have things about ourselves that we might not always be happy to share with everyone for a whole host of reasons. Sometimes because we worry how others may judge us, sometimes because we want to respect the privacy of those who hold the identities that we perhaps don't feel are ours to share. So things like being divorced, having spent time in prison, being an addict, or survivor of addiction or abuse, or having family members to which these or a whole range of other identities apply.
I was chatting with a friend recently about how we wouldn't keep a family member's broken leg secret, so why would we about depression. I very much hope that the taboo that has sometimes surrounded mental health is lifting, and so see where she is coming from and yet am also aware of the complexity. I feel much more able to be open with people about my own experiences of depression than I would feel able to talk about the identities of people in my family and how this impacts on me, as it doesn't always feel ok to share their identities that they may prefer to keep private. But where does that then leave the people who are struggling with that double whammy of coping with a difficult situation yet also not able to be open about it?? Further isolated. Not sure what the answer is...