Person X demands unquestioned loyalty but is disloyal when it suits him. What kind of doofus would be loyal to X?

It depends on the relationship between the two individuals.

If they are equals then loyalty is a two way street.

Though if one serves the other, then loyalty is the duty of the servant. 

If the servant loses faith in the master then he should resign. If he continues to serve but tries to undermine his master, he's a traitor. This post was edited by Zeitgeist at September 13, 2017 11:04 AM MDT