What to do when people you consider friends continuously rail you with impressions of insincerity?

Friendships are the byproduct of human-beings being stuck to live together. The most crucial element of a friendship is "trust". If there is no trust there could be no relationship of any sort.

Human nature has a huge tendency towards aggression and stepping over the boundaries. That’s a fact. Period! Responsible parents control their kids by the virtue of proportional reward and punishment, healthy societies require governing laws to control the public in order to keep them honest, but what controls the aggression and insincerity in a mutually-governed friendship where there is no statement of superiority?

The answer is "Manners". Manners are our awareness of the feelings of others. In friendships, there is no tangible tool to control the other party’s behavior,  so level-headedness and balanced behavior become individuals’ responsibilities. Believe it or not, in modern days your friendships are the only venues available to you to realize whether or not you’d be a fair, just, and adequate queen if you were born a princess. Tough luck! You were not born a princess but at least you can choose to be sincere and unpretentious.