My big nightmare is that it's all a charade and that people are lying to me about what they think of me, because they want me to feel good or just from social protocols. You know, I'm nice so they feel obligated to reciprocate in that. I realize that it doesn't make sense (where did those social protocols come from? somewhere) but that's because people don't make sense.
Most of them probably are, yeah - most people probably have no real opinion of you, so why not say something positive? But then, from what you've described yourself, anyone who actually knows you would know that there's not really any benefit to be gained from being dishonest, and the social expectations evaporate pretty quickly after prolonged contact. Usually a few months will do it - if you've seen someone at least once a week for several months, what you'll have left will be generally pretty honest. The more often you see them, the more honest it's likely to be. Except in the case of the extreme social manipulators, but those aren't common - statistically, you are unlikely to now all that many of them. (And obviously opinions are subject to change based on environment and circumstances - this is why many people hate their exes, and why being nice to people ACTUALLY LEGITIMATELY makes them think better of you. Context!)
I know this from the other side - My problem is that people
don't actually like me as a general rule. It's basically just my brother and my wife. It's why I have to get a new batch of friends ever year, or rather why I had to, because I mostly don't bother anymore.
So I can tell you from that end that they will fake it for at most a year of prolonged contact and after that they just won't be able to fake it anymore, especially since their seems to be little value from you in the eyes of the social manipulators who might stay on longer (You aren't super wealthy and don't have powerful social connections, I believe) Most people will NOT even last a year though - three months is pretty normal. I just do a lot of pretending, which can certainly drag it out. Easier that way. Better to have to make new friends every year instead of every 3 months.