Those are all good points, WC about protecting privacy, which is the main reason i avoid facebook and instagram and only have an anonymous twitter account which only focusses on one subject.

I don't use the same usernames on different forums unless they are on the same subject. I don't tell people my usernames and leave out lots of details when I post. I think it takes an odd person to go poking around on mental health forums to see if they can find someone they know but there are lots of odd people out there and I am sure it happens at least occasionally.