How can I stop co-workers from pitying me because of my chronic illness?

Tell this to colleagues whom you believe need a better understanding of what your experience is so they can give you the support you want and need:

I’m not looking for your pity, or even your sympathy. I don’t feel sorry for myself, and I don’t want you to feel sorry for me, either. But I do welcome empathy, such as, “I understand this is tough.” And once in a while, it’s really great to hear your words of encouragement, such as, “You’re doing a great job with this.” (But please only say it if you mean it).