Well... I'm an older person. I lead a solitary lifestyle. Basically I don't want anything to do with anyone in real life. It works for me at this stage of my life. So my personal opinion is that if keeping to yourself works for you... great! There's no law that says you have to be out "mixing" in society.

Of course where the problem comes in is if you really want to be out in society, but you're hiding out of fear or anger or whatever. If that's the case, then I think you really do need to try to figure out a way to get out into the world-at-large, such as volunteering or something else.

The world-at-large is far from a perfect place. (You already know that.) There will always be some people you'll run into, from time-to-time, who will do the sorts of things you talk about in your post. So if you're going to be out-&-about in the world, you have to learn ways of coping with these sorts of encounters.

One important way of accomplishing that is to just be out there having all of the experiences people have on a day-to-day basis & figuring out what works for you & what doesn't. A lot of it is simply a process of trial-&-error. As the saying goes... practice makes perfect. Well... perhaps it doesn't really make "perfect". But, over time, it does help one to develop the interpersonal skills one needs to be able to get along. At least these are my thoughts with regard to your post.