iPhone photos app crashing consistently with large iCloud photo library beta - how can I completely remove?

Hi - I turned on the iCloud photo library beta on my phone weeks ago. Worked fine with no issues. Then the Yosemite OS X beta 10.10.3 was released with the new Photos app. Once i loaded that new app, it converted my Aperture library and began to upload around 75,000 photos.

My iPhone almost immediately became sluggish (I assumed because it was downloading the pictures) and then eventually started crashing every time I go into the app (after a few seconds). I assumed it was because it showed 75,000 images in my Cameral Roll/Moments so I turned of the iCloud photo library beta. It prompted to be certain I was ok with deleting the images, which I said OK to. But it still shows 75,000 images in the camera roll and anything I tried to do with any photo has become completely unusable (generally just crashing each time).

Did I miss a step in the process?

Is this just me?

I'm trying to backup my iPhone but it keeps erroring out with the message "iTunes could not back up the iPhone "name" because the iPhone disconnected". Otherwise I would just recreate . Please help