I tend to have my guard up with people who ask me personal questions. You can't possibly gauge how the person will use the personal information that you choose to share with them. There's just not fool proof way to protect yourself from gossip or slander, even if you choose to remain mum. People will do or say whatever they want about you, no matter what you do. I realize that's not the answer you're probably looking for but it's the sad truth.

I don't feel isolated from people if I don't share personal information with them. You can have a pleasant connection with someone on a superficial level without delving too deep about your personal life if you really want to.

If you take a risk and disclose personal information about yourself here on the public boards, or in PM with a PC member, you have no control with what happens to that information. That's just human nature. People either respect your boundaries or they won't. No way to forecast who will respect your boundaries or who won't. You just need to take the risk. That is the only way to find out who is trustworthy and who isn't. Based on how they respond. If you reach out to someone and he/she refuses to open up, it could be because they don't like or trust you, or they don't like or trust anyone.