Nostalgia?

Quotation
"And was the day of my delight
     As pure and perfect as I say?
     The very source and fount of Day
Is dashed with wandering isles of night?

If all was good and fair we met,
     This earth had been the Paradise
     It never looked to human eyes
Since our first Sun arose and set.

And is it that the haze of grief
     Makes former gladness loom so great?
     The lowness of the present state,
That sets the past in this relief?

Or that the past will always win
     A glory from its being far;
     And orb into the perfect star
We saw not, when we moved therein?" -Alfred, Lord Tennyson, "In Memoriam
                                                                                          A.H.H.: 24"