The Aging of Grief

I'm currently slogging through The Brothers Karamazov.  Yes, I do mean slogging.  It's not an easy read, but it does have moments of brilliance.  This morning, this line made me stop and ponder for some time:

"It's a great mystery of human life, 

that old grief passes gradually into quiet, tender joy."  

I do think that's true.  And miraculous.  Even the sharpest of life's pains dull over time.  Thank goodness for joy, and that sorrow is only a periodic visitor.  But how "old" must the grief be before you can stop nurturing it like a sick child and kick it out of your house?  That's what I want to know.

Speaking of books, aren't these book sculptures (what the artist, Brian Dettmer, calls "altered" books) clever? (discovered via Omnivoracious)