Misophonia is a very rare disorder that affects a person's sensitivity to noise. The word
misophonia literally translates to "hatred of sound" and sufferers of the disease often have violent reactions to a certain set of sounds they call "triggers." The sound of people eating and breathing are some of the noises that trigger a reaction for people with misophonia.
Oh, so that's what my boyfriend meant when he said, "it's not you, it's me!"