The thing about invisible chronic illness is just that - it's invisible and so it doesn't register on others how much it affects us. A personal example: when I travel by air I get a wheelchair to move around the airport because it's very difficult for me to walk any distance if I'm also lugging bags. I can do it - slowly and with considerable difficulty - but there's a price in pain and mobility to be paid later. I feel embarrassed being wheeled around. After all, I can walk albeit slowly and it's not pleasant being dependent on others however kind they are but, if I don't use the wheelchair, I'm storing up a huge pain deficit to be dealt with later, one that I can't really afford especially if I'm travelling somewhere that I need to be able function well.
Have a read of these posts. I'd be interested to hear what you think.