"How are you?" many ask me.
"Fine," I lie with a bright smile.
"Terrific, I'm glad that you are doing better. I'm glad that (fill in the blank) is working for you. I've been so worried."
Or on the phone they say, "Oh, you sound chipper! I'm so glad you're better. I've been so worried."
Years of training in customer service have taught me how to sound good on the phone regardless of how I feel. Even though I want to strangle the customer I'm smiling as I speak. Years of frightening or worrying my friends and family have taught me to sound positive when answering the "how are you?" question. Years of feeling lousy have taught me not to push my negativity onto others. Years of living with my good, caring husband have taught me that I should be a good, caring person, also (or try to be). Regardless of how I feel.
I saw a button somewhere (and help me find it again if you know where it is) that said something like, "I look good, but you should see my brain!" or "I may not look sick, but you should see my brain."
It's not helpful to tell everyone everything. And dealing with other people's reaction to "I feel like crap" can be just as exhausting. "I'm not strong, I just can't deal with your reaction." We feel that we have to comfort the people who get upset when we are feeling bad. So we filter our responses, we are cautious with our words. It saves relationships, people don't avoid us, people enjoy our company.
And there's nothing wrong with that.