Ok, do you have frames for the pictures? One evening, grab some of the pictures, and select a few as your favorites. She might help with going through them. Anyway, put the ones you choose in frames, and hang them. The dollar stores here used to carry a good selection of frames that didn't cost an arm and leg. Salvation Army thrift store, and another local thrift store usually have lots of them, and they're inexpensive. I got the hardware to hang them at Home Depot.
Michael's tends to have scrap books, and the sticker tab things to hold the pictures on the scrap book pages. That's a good thing to do with the ones you don't want to hang. Next time you go somewhere with her, have her pick out one or two, and some of the sticker things that hold them to the page.
Maybe having the supplies to help get it done, will empower her, or inspire her, and she can get it done.
Or Bruce could just go ahead and hang them up where ever HE likes and she will be sure to have them relocated where SHE really wants them

Funny how someone who can't decide will finally do so when someone else makes the decision for them.