In the same way that lifting your arm is different than thinking about lifting your arm, I imagine you could train your mind so that transmitting a thought is different than thinking a thought. And hopefully it would turn off if you fall asleep.
But yeah, who knows, maybe the two processes will be so distinct that it's not an issue.
Slip-ups would definitely still happen, but I think they would be more expected and less of a big deal with such a fluid communication system. And maybe you could build in a delay that reads your thought back to you before it sends.