The Paradox called Love

... love involves (tragically, incorrigibly, but also beautifully) a desire for something that continuously transforms. Love is painful because we want the object of love to change and stay the same, love is a desire and a fiction that animates our greatest pleasures and our most profound sufferings. Love hold us to this life, keeps us faithful to it. Yet nothing can save us from our ultimate reentry into oblivion - the point at which no amount of consciousness or desire can preserve identity or the energies that we once called our own.

-- By David LaRocca in the afterword to Schematics: A Love Story.

I found this quote at Brain pickings