Whosoever Shall Offend by F. Marion Crawford

Two years had passed since Marcello had been brought home from the hospital, very feeble still, but himself again and master of his memory and thoughts.

In his recollection, however, there was a blank. He had left Aurora standing in the gap, where the storm swept inland from the sea; then the light had gone out suddenly, in something violent which he could not understand, and after that he could remember nothing except that he had wandered in lonely places, trying to find out which way he was going, and terrified by the certainty that he had lost all sense of direction; so he had wandered on by day and night, as in a dark dream, and had at last fallen asleep, to wake in the wretched garret of the inn on the Frascati road, with Regina kneeling beside him and moistening his lips from a glass of water.