my situation may give you some insight.
I was raised by/with my grandparents. they seem nice, they act nice, they don't hit me but something is still wrong.
they have subjective principals, they can never admit fault and they only apply thier principals/rules when it's convenient for them or to save face.
They never actually respect my choices when I have complete freedom and authority over something in my life but they want something else and instead of actually talking to me about it they just try to manipulate me into doing and keep pushing untill I cave in.
they're also complete random and hypocritical, like one day they'll insist on throwing out a blanket i like because it has a hole in it, I'll beg them not to because i like it and it's mine anyway and it's just a blanket, it's not like it even matters to them or inconveniences them in any way, but i like it, but that's not enough for them, so after pushing untill we have a fight, they just throw it out anyway. Then in a few, weeks, days or months they'll be like >"where's your blanket, possum?">"i threw it out?!?! we'd never do that, that belonged to your auntie Eidith, it was practically an heirloom!"
at which point i explode into rage and they get all upset like>"why are you so angry? :((((((((">"it must just be in the linen box, lets go check"
Interacting with them is at first pleasant, seemingly nice, all smiles, but eventually descends into just a confusing minefield of red herrings, subjective principals that they will forgot about tomorrow, random disrespect of me or my possessions, hypocrisy and stubbornness- and i haven't even figured out half the logical fallacies they engage in yet. i gotta review this image a sec ...
anyways my point is, people can seem nice, they might not hit you or anything, but people can be unbearably retarded to the point of passive destruction.