You're not the first . . .
Dr Alan had slept with one of his patients and felt really guilty.
No matter how much he tried, the sense of betrayal was overwhelming. But every once in a while he'd hear an internal reassuring voice say, 'Alan don't worry about it, you aren't the first to sleep with one of your patients and you won't be the last. You're single, just let it go.'
But invariably another voice would bring him back to reality whispering, 'Alan, you're a vet!'