There's two kinds of people: those who have connection with you and those that fake it to gain your sympathy

Trauma reshapes the brain into rigid sectors, or rather it compartmentalizes information depending on how deep you feel the emotion. Emotion bonds the experience to memory. The stronger the emotion you had, the more powerful the memory and the more your brain is shaped to accommodate it. You might not remember the details of a certain memory but you probably remember how you feel about it

Let's say you have a connection to a certain person or type of person but it was unexplainable for years and years. You just know that you get them and they get you, even if you're only seeing this person in passing and for a few seconds you see them and they see you. And no other words need to be said. You both share the feeling and thoughts.

Let's say you both have had rough childhoods or upbringing. That would've reinforced the way you had to think, thus creating very predictable thoughts patterns for yourself.. so when you see another person who gets you.. it's because they had to think the same way to tolerate their situation. You both think similarly because you both had similar thinking styles for years due to the upbringing. That's the connection and why you get that stranger and they get you, instantly. This could be similar to why when you meet a girl, she gets you and you get her. Both similar upbringings resulting in similar thinking patterns through and through. A common ground of shared trauma, maybe

If Post comes off as bs, because well it likely is, but it's fun to think about there possibly being a reason or underlying logic to it

If you ask a biologist, they will claim humans are very predictable creatures. I wish I studied this stuff more