In the end, we all have our own threshold and tolerance about people, society, and who we bring into our lives. The upshot is to be wiser and more intentional about everything in our lives period... which very much includes who we let in. ---Not because they could harm us, but because with EVERY human we get close to, we naturally inherit their good and bad drama. We are all, to some degree empathic, so we can't help absorbing a part of each spirit we get close to. The question is, are they worth it? This takes careful vetting.
The trick is to learn to separate who's 'luggage' is whose. LOL
Are you the co-traveler or the porter?
I have a few rules that work for me.
1. Go slow and declare your love of privacy up front: Most people have alarmingly little appreciation for it and think nothing of violating personal space in this SM age. If you don't (use humor) to state your boundaries, no one else will. Nothing wrong with declaring that you're a die-hard loner.
2. Be careful of the need to "help". There's an enormous difference in giving an opinion WHEN ASKED, and needing to give advice to be, well....needed.
3. Make note of the 'spinners': People who ask for your advice but never take it, then ask for the same advice again. They are takers and have no intention of doing the required work to grow and end up making you their babysitter. Those who what to know more about the advice you gave are seeking clarity and are worth your mentorship.
4. Be social with people out in the world, but be careful who you let into your inner world. Have a few dinners out with people to see if you really connect. Do something public with them (farmer's market, shopping, etc) and see if they connect with what you connect with, before bringing them into your inner sanctum. Once they're there, it's so much harder to close the door.
5. Don't give out your personal numbers until you're convinced that a call or an email from 'them' will be welcome at any time when you least expect it.
6. Never get hoodwinked into "reciprocating" when you're not ready or don't want to. If you must, then do it away from your own home.
7. Better to be a bit mysterious and unfold to people over time then to blurt out who you really are to people who aren't really listening, or who are more nosey than interested. Remember when you're out in the world you're on record and on "camera."
If we are hell bent on hiding from the world altogether, that's not emotionally healthy. By the same token, we should never force ourselves to be what we're instinctively not either. There are far more introverts on this planet then there are extroverts.
Many introverts (like me) are very comfortable and engaging out in the world but by nature are private if not shy. For a very long time introverts got a very bad rap. We now know there are many degrees of introversion and no set rules (AT ALL) as to how much "social integration" one person needs versus another. If one is frightened of people, that's a phobia. If one is discriminating and careful about people, that's altogether different and prudent.