People tend to have their own feelings about what behavior or conversation subjects are polite or rude. Is there a specific term to refer to a person's personal definitions of this? The terms "ethics", "morals", and "virtues" don't seem specific enough in dealing just with this sense.
I believe the word you seek is 'sensibilities.'
Receptiveness to impression, whether pleasant or unpleasant; acuteness of feeling. Often used in the plural: "The sufferings of the Cuban people shocked our sensibilities" (George F. Kennan).
The implication is that some other group may not have their own sensibilities shocked by the same thing. It then follows that "One's own sensibilities" would determine what an individual perceives as polite, rude, annoying, etc.