sugahorse, maybe explain to them that, when they ask how you are and you say OK, that that's OK RIGHT NOW - you'll do everything to stay OK, but you may not be at different times, due to brain changes that you can't help. If they care enough, they'll listen. If it's a really important person, you could ask for them to come see you with your psych team and they can ask questions.

I bailed on a friendship of 30 years last year because it became terribly obvious that she was expecting quick fixes with my illnesses, which are life threatening and through which I nearly died. - and which will be lifelong. I mean, she was there in ICU while I was in a coma, but in the months following that she still expected me to suddenly get up, dust myself off and say "I'm not going to be sick anymore" (paraphrasing). In the end I found her to much to bear ironically. I've tried to see it in a non-combatative way and say to myself that my limitations were coming up against her limitations and something had to give. Which it did.