I know that I don't share what's going on so that I don't burden my family members, esp DH, who has more than his share to carry with his parents lately.
For instance, he said the other day, "You're walking really well." I told him that he doesn't know the mental energy it takes to make sure I am lifting my bad leg, not walking like a drunk, etc etc.

The emotional roller coaster ride is also something I try not to share, although DH's shoulder is always available to cry on...I could cry for hours if I let myself...just part of the disease for me. I get overwhelmed easily, the brain fog is frustrating at best, and I just need to boo-hoo to rid myself of the rotten feelings.
When I say to a friend I haven't seen for awhile, "I have MS," I get the usual "You look great...you don't look sick at all," I smile, nod, and thank my lucky stars that I have a place like this where people truly do "get it."