Ok, plan 'B'.
In your '~/Library/Applications Support/' folder should be an 'Address Book' folder.
Quit 'Address Book', if already launched.
Click on the 'Address Book' folder and make a duplicate - 'Command D' or 'Finder' 'File, Duplicate' menu item. A new 'Address Book copy' folder will result.
Open the (original) 'Address Book' folder and then its 'Images' folder. You should see at least one file in it, with a size greater than 4 KB (in 'List' view mode).
Click on the 'Images' folder and rename it 'Images_'.
Launch 'Address Book' and again, try to assign pictures to Address Book entries, including the current user. Success or failure?
If failure, somehow the 'AddressBook.data' file may be corrupted. This I currently do not know how to resolve.
To verify the 'AddressBook.data' file is corrupted.
Quit 'Address Book', if already launched.
Click on the 'AddressBook.data' file and rename it 'AddressBook.data_'.
Launch 'Address Book' and again, make a few entries and try to assign pictures to some of the entries, including the current user. Success or failure?
If successful - the 'AddressBook.data' file was corrupted.
If the 'AddressBook.data' file is verified as corrupted ...
Quit 'Address Book' and delete the 'AddressBook.data' file.
Rename 'AddressBook.data_' as 'AddressBook.data'.
(optional) Delete the contents of the 'Images' folder.
Launch 'Address Book'.
Select all the items in the 'Name' column.
Select 'Address Book's 'File, Print...' menu item.
Select 'List' from the 'Style:' popup menu.
Click on all (or what you want of) the 'Attributes:' list check boxes.
Make any other personal selections.
Click on the 'Print' button.
Quit 'Address Book'.
Click on the 'AddressBook.data' file and rename it 'AddressBook.data_'.
Launch 'Address Book' and start re-entering all the names, assigning photos, etc.