I think I know how you feel. I've heard lies come out of my mouth when I (the core?) am scrupulously honest.
I used to sing in a church and suddenly lose the melody (I sang lead).
Other times I would sing the harmony part instead of the melody and I can't even sing harmony. well, obviously, one of us does!
This is all so new to me. My parts have been hiding for so many years, except for Baby and Toddler.
In some ways it's scary and in others it is so cool. I have--am--a team. I am not alone.