A number of years ago, I was with dear friends, a married couple who'd both struggled with a variety of medical problems for years, when I began to feel unwell. I had just been diagnosed with hypertension, and though that's said to be asymptomatic, my own experience makes me wonder how true that is. I apologized to my friends for my wimphood, and the wife told me not to worry, saying "Everyone's pain is their own."
I've been thinking about that statement ever since, and I think it says something important about chronic disease. It's just not possible to tell by a medical chart just how ill a person feels - our bodies are just too complicated for that. And, of course, we are much more than just our bodies -- our emotional health at the moment, our spirituality, and our attitude can all dramatically effect how "sick" our disease makes us at a given time.
This is part of why I feel it's important to do what we can to back each other up, as diabetics in the DOC and also as human beings in the world. People don't wear "pain-ometers" that tell others how much support is needed at a given moment. A kind word or small favor to someone who's expressed no distress at all may have been deeply needed.
Finally, there's no reason to feel disappointed in ourselves because we're having a bad day, or week, or month. How we feel is how we feel. Everyone's pain is their own.