My eldest sister had CFS for years before I got sick. When I came down with it, she kept telling me it was CFS, but I was in the medical profession and had long since concluded that she was neurotic since all she ever did was complain about how bad she felt, and how no one understood how sick she really was blah, blah, blah. I totally ignored her illness for all those years and I was really annoyed that now she kept insisting that
my very real, very serious and very frightening symptoms were the same as her imaginary illness.
Then at one point after having every test in the book all come up negative, my boyfriend at the time (an ophthalmologist I had been dating for years) very cautiously and gingerly said to me, "Ya know, there
is one thing that could be doing this to you, and it's really the only thing that fits now." "What's that?", I asked, wondering why in God's name he hadn't mentioned it before. He hesitated for a moment and then took the plunge, "Chronic Fatigue Syndrome"
And just as he figured I would, I flipped! I almost slapped the poor guy and replied while practically foaming at the mouth, "You SOB! Can't you see I'm sick here? What's the matter with you? How DARE you say such a thing you insensitive #%&*@!...." and that was just the warm up. Turns out he was right, and my sister was right. Yup, I had a little egg on my face on that one. Glad they were able to forgive me.
Some years later when our middle sister also got sick, she had her elder and younger sisters both trying to convince her that she had our disease and she needn't continue to subject herself to the futility, expense, discomfort and emotional anguish of consulting still more doctors and undergoing still more testing, just to get still more 'normal' results. Naturally, her response to us was often something along the lines of, "Geez! you know what think? I think one of the symptoms of having Chronic Fatigue Syndrome is thinking everybody else has it too!" Of course we completely understood her reaction.
Most fortunately, the Internet had become a part of everyday life by this time, so it didn't take her long to figure it out for herself and realize what was happening to her, and to finally understand what her sisters had been going through as well.