Oh, it's so hard! I don't blame her.
We went to a downsizing seminar given by the guy who hosts the Hoarder's tv show. The most important thing he said was we're in a strange scenario today with so many different generations living: those who went through the depression, their children who learned to "save everything in case you ever need it", and the younger generation doesn't want the stuff at all, only throwaway IKEA junk. It's especially hard when everything we have reminds us of someone who's gone, which the kid's don't know or remember. BUT the silver lining is that the kids want the MEMORIES in place of the stuff. Take a photo and write the story. Tell the kids about things, show them places, etc. - but make sure it's documented. So, that's what I'm trying to do. Knowing all that has helped me go through things. My DD wants nothing, and if she does want anything it'll be a decade or so from now. She left the house and took nothing - only wants new things that are "hers". My DS, on the other hand, wants anything we can give him because it's free, but he's a minimum of 5 years away from moving out. So, lots of stuff!
I like the Fly Lady and her 21 Fling Boogie: Take a bag and go around the house and put 21 things in it that need to go. It can be 21 chewed up pencils or 21 broken rubberbands, but it gets you used to sorting through things quickly when you need to do it.
But I still can't let go of the leaf, twig and crayon drawings I made when camping in the Redwoods when I was five years old... and I'm approaching 60! lol!