The Wave by Algernon Blackwood

Yes, she was always 'tired' now, though the 'always' meant but three days at most. It was the starving sense of loneliness, the aching sense of loss, the yearning and the vain desire that made it seem so long. Lettice evaded him with laughter in her eyes, or with a tired smile. But the laughter was for another. It was merciless and terrible -- so slightly, faintly indicated, yet so overwhelmingly convincing.

The talk between them rarely touched reality, as though a barrier deadened their very voices. Even her mothering became exasperating; it was so unforced and natural; it seemed still so right that she should show solicitude for his physical welfare. And therein lay the anguish and the poignancy. Yet, while he resented fiercely, knowing this was all she had to offer now, he struggled at the same time to accept. One moment he resisted, the next accepted. One hour he believed in her, the next he disbelieved. Hope and fear alternately made tragic sport of him.