4 KudoZ points awarded for this answer. Comment: "I came across this term yesterday reading the cited article and felt stumped as to how it might be translated into Spanish. To me, the main idea that needs to be conveyed is that Trump’s attitude toward Tillerson, which had previously been positive, had turned negative. For this reason, solutions such as “se ha deteriorado,” “ya no sintoniza,” and “se ha distanciado” really do not work. These options allow the interpretation that the relationship has deteriorated as a result of some difference of opinion or philosophy, when the clear meaning of the English is that Trump’s attitude toward Tillerson has changed for the worse. In this light, “agriarse” is an interesting option. The problem is that it does not seem to be commonly used as an intransitive verb *to convey one’s attitude toward another person*. Thus, while “Juan se agrió” or “La relación entre Juan y Pablo se agrió” make sense, “Juan se agrió con Pablo” apparently does not (or, in any event, does not represent standard usage). And the problem here with “La relacion….se agrió” is that it does not convey the core idea of the source that Trump’s attitude turned negative. This leaves three possibilities: “la desafección de…,” “se ha perdido la estma por” and “se ha desencantado con.” I think that all of these are good, although I somewhat prefer “se ha desencantado con” because it seems to more accurately convey the emotional charge of the English “soured.” Many thanks to all who offered suggestions to and commented on this post. "