Someone that doesn't suffer from these things just doesn't understand. My husband has REAL health problems (diabetes, gout, etc) and if I start complaining thinking I have MS or colon cancer or some such thing he just says, "You don't have anything, you are the healthiest person I know, I don't know what you'd be like if you had all MY problems!" He doesn't understand that OK yes, healthy now, but one day one of these symptoms WILL be the REAL thing! I just don't know which one or when it will happen so I have to worry and stress over EVERY ONE.
Or I'll say, "I feel real weird, maybe something is happening!" He just grins and says, "Take a xanax" (Actually that makes me feel better when he says that because I figure if he isn't taking it seriously I must be OK)