Siegfried Sassoon - Sick Leave

When I’m asleep, dreaming and lulled and warm,—
They come, the homeless ones, the noiseless dead.
While the dim charging breakers of the storm
Bellow and drone and rumble overhead,
Out of the gloom they gather about my bed.
They whisper to my heart; their thoughts are mine.
‘Why are you here with all your watches ended?
From Ypres to Frise we sought you in the Line.’
In bitter safety I awake, unfriended;
And while the dawn begins with slashing rain
I think of the Battalion in the mud.
‘When are you going out to them again?
Are they not still your brothers through our blood?’

Siegfried Sassoon

http://www.poemhunter.com/poem/sick-leave/