I am having this same problem. I'm at work and my Nook is at home, but if you go into the Menu (the top bar), there is an option that you can uncheck that says "Google Sync Accounts" os something similar. That may stop it. Other than that hopefully someone else knows.
Is this update from Nook or Google Play?
I get something like this from Google Play. what the earlier poster said might help. It must be a Google setting somewhere to not sync Google Library.
I was having the problem with the same apps bought through Nook and Google Play (Twitter, Spotify, etc) trying to compete update. Deleted Spotify as I never used it and then did what everyone suggested already here by going into settings in Google Play (three small boxes in the top right hand corner) and on the 'Auto-update apps' pressing on it to bring up a pop up box in which there is an option to NOT be notified about auto updating. Solved my problems. Good luck!
Someone did explain how to pull up the sync button in the Library section (volume up and tab on the word Library at the top). Perhaps doing this will at least give you some control over the sync.
Thanks celandinehobbit..tried the volume up and tabbing on the word library and the syncing symbol now appears on the top. Hopefully this will solve crazy syncing. Will update post if problem persists.