"No photos or videos" after move to iCloud
My complete photo library (112k images or so) is now in Photos on iCloud. My two computers are in sych with each other and with the cloud (yay, it took all month). However, my iOS devices (iPhone 6, iPad mini 3) no longer add new images to iCloud, even though I have iCloud photo sharing turned on. Not only that, but the photo libraries flash into and out of existence - if I open Photos on my iPhone, it shows 300 photos in my library, which then starts dropping until I get "No photos or videos " on a blank background. Then photos reappear, counting up into the thousands sometimes before crashing back to zero again. This cycle repeats endlessly. I tried to allow the devices to sit overnight with the photos app running, in case it is a problem with the images loading in the first place. However, this had no impact on the cycle.
If I try to click on an image to show it to someone, the app crashes.
Both devices are running iOS 8.3. I have restarted both several times. I have followed the only recommended fix for this (turning the iCloud photo sync off without downloading photos, restarting, then turning it on again) and the problem persists. It has been this way for several weeks.
Help! I would very much like my new photos to start uploading again, and my old ones to stick around reliably so I can show people. What can I do?
iPhone 6, iOS 8.0.2