if I start thinking about something besides what I'm playing for a second, I lose concentration, focus, and ultimately my place in the song.
I think the answer lies in your problem. You say if you lose concentration, such and such happens, well, don't lose your concentration (easier said than done, I know). Immerse yourself in the music. Get lost in it. Go into your own little world where just you and the piano and the music exist. And practice doing that when you practice playing. Close your eyes and block everything out. It'll quickly become routine, and you'll just do it automatically, even in front of large groups (with the aid of a few deep, calming breaths, maybe. Even non-wind players have to breathe!). It'll become so natural that when the audience breaks out with thunderous applause, it'll surprise the hell outta you because you forgot they were there.
That's my way of doing it. The more I'm into the music the less nervous I am. If you think about who's out there and what they think you can't "Immerse", great word, your self in your music. Just relax when you play.* goes back to own little world*
I totally agree with that. If you're playing piano, block everything out completely and concentrate soley on the music. That's what they want to hear and that's what you want to do and that's what's most important. And if you're singing and you're in front of a lot of people, just completely look past them. Stare at a back wall and ignore every person in the theater. Sing like you're by yourself in the shower and come back to reality just long enough to hear the applause.
