A teenager has revealed that he has never eaten Christmas dinner with his family due to a rare condition that leaves him enraged by the sound of people chewing. Grayson Whitaker has lived with misophonia, a condition that causes an extreme emotional reaction to certain everyday noises, since he was a child. The sound of people breathing, yawning, sniffing and chewing fills the 19-year-old with anger. He can't even enjoy a Christmas meal with his parents Alex, 51, and Dawn, 54, as he locks