Well,
I have been told to stop playing for people before, and it does make the musician feel bad, as if they can't play, in which is a reason why if I don't practice with you beforehand I will not play with you now. Musicians do not know every song and we can't play a song the way everyone wants us to play it, especially when we haven't heard the song before, or know how the singer(s) is going to sing the song. to me if I don't know what the singer is singing or how they are going to sing it, I sit the song out, even when they say come on musician help me out, because when they begin to mess up, then the first thing they are going to say is that musician threw me off key or off beat, so it is better not to play for me. I think that since she is a musician she should have got on the piano and played the song herself. No offense, this is just my opinion.