::gentle hugs:: with invisible illness, it's bound to happen sooner or later. Doesn't make it any easier to deal with though. It hurts, and it pisses me off, too. A few times when this happened to me, I printed off a bunch of info on fibro and CFS and arthritis, and SI joint dysfunction (I think that's it lol) and handed it to them. Told them to read up and get a clue. I don't think they talked to me after that.