I actually disagree a bit. I feel like if they cared, they would listen. And continuing to ignore what you explained is not listening/caring.
Luckily, I have people in my life who care and listen. I'm also pretty outspoken (but not rude ) and if someone handed me an article on IBS, I'd hand it right back and say "I dont have IBS" and leave it at that. Or I'd hand the article back (raw food diet) and say, "What are you trying to kill me?" while laughing (to put them at ease).
I also do what Nanners does, I always say Crohn's Disease, rather than IBD. I could probably count on one hand the number of times I've said "I.B.D."