If it's an once in a great while incident where people will make little comments about someone's bo, it's probably due to normal bo.
But if people make comments about the odor within earshot of you or people sneeze, cough, get sore throats/burning sensation in their throats, or don't feel well around you on a daily basis, it's not in one's head.
Some of us don't smell ourselves. On rare occasions I can smell myself, the room I've been in has either a sewage smell or an indescribable strong pungent odor.
Why can't our families smell us? It could be less stress which in turn causes us to sweat less. It could be something genetic that they can't smell us. Perhaps it's because we aren't in the small confined area for 8 hrs. in the house as opposed to work. Maybe the family has a bad sense of smell.
Why can't the doctors smell us? They're lying, they have a good ventilation system in their offices, or they have a bad sense of smell. It might be that they can't smell us because we're in the examining room for 5-10 minutes and it's not enough for the odor to start accumulating.
True some people will think it's all in their minds but external cues on a daily basis will tell you it's not in your head.