Yes, I've been there before. Sometimes I have gotten up and helped the person. They watched me walk stiff; I told them I have a muscle disease and then it wasn't so bad, but there have been plenty of times where I just sat there, kind of put my head down, and felt horrible about it.
Sometimes I am just too tired to get up and help someone do something physical. I think in my mind that they are just going to have to deal with it, but I still feel pretty bad. There are other times when I am too embarrassed to get up and walk in front of the person--can't be strong all of the time.
I guess I just chalk it up to sometimes life is unfair and sometimes life does just kind of suck. It is the reality of my life that I have a muscle disease, so I just have to deal with it.