MH, Empathy and Support
I am sorry you are bothered by nosey people. When they ask the questions that are none of their business, you might try saying: "Now, why would you ask that"? That can throw it back at them.
I am the last person to help with the nosey people problem unfortunately! I am a totally open person (too much, I'm told) and can't really understand why people want to keep who they really are to themselves, when we will be on the other side soon, where everyone can see every thought you've ever had in past, present and future lives and every deed you've ever done.
Yes, my openness is one reason why I get hurt so much, but it also allows me to sift out the bad guys quickly, since they come in for the kill quickly when they see I'm so open. Now that I have more ability to read them, I agree with you that I won't need to be as open to weed them out, so I will have to learn to zip my lip like you do. I also can't read people I can't see, so I will be much more cautious with online friendships. Since I am homebound now, they are an important part of what is left of my life, but after recent events, I've cut my computer time in half, and am focusing more on other things.
I have the opposite problem from your nosey people problem! Nobody wants to ask me anything, unless it's to dump their personal toxic family stuff on me once in a blue moon when they can't find anybody else. I can't get a good conversation going for the life of me, except with my spouse, and I thank God for him. People actually seem to be afraid of me when I bring up a topic that interests me and that requires having an open mind, like UFOs, time travel, parallel universes, etc. It's like using a few brain cells might kill them, lol! I make friends with online people who act like they love discussing these things, but as soon as they get comfy, all attempts to discuss things that matter are ignored, and the same old personal stuff starts that I could get from talking up one of my neighbors.
I am also subject to the INFJ fade, if you know what that is....happens to me all the time, even with new face to face friends. Other women meet me and act like they are in love or something, bringing me flowers and presents and throwing compliments about how kind and caring and spiritual I am. It's ridiculous, since I am flawed like we all are. Then, they slowly find out I won't go to loud concerts, or to the beach (crowded and very hot) shopping (I'm not materialistic at all and can't stand crowds), I won't watch romance movies, and I want to BE rather than DO. I want to talk about things they have never heard of, ie. I am an egghead, a brainiac. So, they slowly fade away, keeping in touch just enough to be able to contact me again if they need help.
Just by typing that, I may have thought of a way to help you with nosey people. Just bring up subjects like I do, UFOs, the paranormal, other dimensions, ghosts, The Nag Hamadi or the gnostic Bible, Tibetan Book of the Dead, anything that will scare them, and I can almost guarantee you it will scare that type of person. I bet they won't bother you again.