I think you're a little quick on the trigger, it's not just cheaters who assume that people cheat, it's also people who have been cheated upon or lied to.
In general, I think this is asymmetrical. People who have never had to deal with complexity in their lives, tend to assume that people can live by simple rules. Until they discover that the world doesn't work that way. Usually by getting their naive ass bitten.
They don't call them realists for no reason. (Yes, I know, spoken like a realist :-)). I don't place much value on the opinions of people who tell me how perfect they or their family is -- usually they avoid digging too far into the fascade because their self-worth is tied to how well they and their group (family) perform whatever role they are holding up as ideal.
In general, I think this is asymmetrical. People who have never had to deal with complexity in their lives, tend to assume that people can live by simple rules. Until they discover that the world doesn't work that way. Usually by getting their naive ass bitten.
They don't call them realists for no reason. (Yes, I know, spoken like a realist :-)). I don't place much value on the opinions of people who tell me how perfect they or their family is -- usually they avoid digging too far into the fascade because their self-worth is tied to how well they and their group (family) perform whatever role they are holding up as ideal.