seeing as you started:
Dave (not his real name) was losing sleep, and he had felt guilty all day long. No matter how hard he had tried to forget it he couldn't. The guilt and sense of overwhelming betrayal were immense.
But every now and then the soothing voice would come into his mind "Dave, you're a single man, you're not the first and certainly not the last Doctor to have slept with one of his patients. Let it go Dave, chill out"
But always the more sinister voice woud creep into his thoughts, the one that brought him back to reality with a quiet whisper :"But Dave....you're a vet!"