Longing

I am winter, that doth keep
Longing safe amidst of sleep. [William Morris]

Longing is fragile, and needs to be protected—to be deep-frozen, like food. But does anybody else situate longing, rather than love, at the heart of the lyric like this? St Augustine's old line about being in love with love is surely actually about being in love with longing ... Morris understands that: but who else does?