Part of the problem is that I love being the center of attention. One sure way to get people's attention is to be a source of information for them. I love informing people about nearly any kind of information, even including gossip, as I want people to listen to me (which is probably why I'm a teacher).
Another issue is that I generally think that information is better shared. I believe this to the point that there are secrets in my life about myself that I have been told (by people who know) not to share with others because of people's prejudices and beliefs. Some of these are particularly embarrassing, but I would prefer for people to better understand me even if it leads to their condemnation and disgust. Still, to spare their sensibilities, I don't share them. I know that part of this desire to reveal all is due to a series of lies that I told as a pre-teenager that caused problems and misunderstandings (some still ongoing) once the lies were discovered.
It's for these reasons that I despise court decisions that impose gag orders or companies that require secrecy (of items beyond the normal trade secrets) from their employees. I know that there are good reasons to keep some things secret, but I still hate the need.
There are some secrets that I keep from more general knowledge because they are not mine to share, but most of those have even been discussed with a number of people whom I care about and trust. Should you tell me a secret, I can almost guarantee that my wife will know within the day. Some of those other friends will know whenever I next see them (if it's something that I think they care about or that I just really need to share).
All that said, I don't want people to keep things secret from me. I like knowing, even if it is something that does not directly impact me or those close to me. Just don't expect me to keep it completely secret for long ...