Tiny Luttrell by E.W. Hornung

The worst of it all was this: that the young man himself had not invariably that confidence in his own affections which displayed itself so bravely and so convincingly at a psychological moment. Not that Manister was insincere, exactly. If you come to think of it, you may deceive others with perfect innocence, having once deceived yourself. And this was exactly what had happened.

There was one distinctive feature of the case: away from Christina Luttrell the poor fellow had already had his doubts of himself; in her presence those doubts were as certain to evaporate as snowflakes in the warmth of the sun.