I do have a problem deflecting my fears or discomfort with humor...but when someone asks me how I'm feeling, sometimes I like to say "Oh, just a little messy! MS-y, get it? Get it?!" I've found it's a good way to tell the truth without complaining about every single symptom (as I am sometimes tempted to do.)
On Facebook once I posted a picture that said, "I'm not drunk; I have MS." I thought it was hilarious because when I do walk, I totally look drunk (thankfully I don't have any slurred speech!) It must have made some people uncomfortable, because they responded saying things like, "Oh what a horrible thing to say! How insensitive! Shows our society is going downhill!"
Failed humor: I used to joke around that I couldn't do anything. Like, someone would say, "Okay can you email me back?" and I would say, "I can't because of the MS" and then laugh. They didn't think it was funny though; because for all they knew, I really couldn't do it and then they felt guilty. So that failed and I don't do that anymore.