IPhoto (old-- version 8?) won't import photos from iPhone 5. Very buggy.

Question

I have an old version of iPhoto that is very buggy (we have an 06 iMac, to be replaced next month). Admittedly, when I've been prompted to rebuild the cache, I don't (what does that do, anyway?). Lately, my problems have been: 1) Certain photos from my iPhone 5 continually re-import even though I check "Don't import duplicates." 2) Most concerning, photos from the past three months on my iPhone won't import to iPhoto. I get an ominous error message after iPhoto takes about an hour to go through the import process. On occassion, random photos (1 or 2) will import. Sometimes an image from a video (but not the actual video). My photos are trapped on my phone, currently not backed up. I have 1000+ photos on my iPhone, as I am sentimental and paranoid and don't want to delete them. Also--our photos are on an external hard drive. We also use TimeMachine and back up on a remote server through a service. I could live with losing everything on my Mac...but not my photos. The over 10K photos are painstackingly organized by folder and albums. Help me!!!

Answer 1

Apply the two fixes below in order as needed:
Fix #1
Launch iPhoto with the Command+Option keys held down and rebuild the library.
Select the options identified in the screenshot. 
Fix #2
Using iPhoto Library Manager  to Rebuild Your iPhoto Library
Download IPhoto Library Manager 4 for OS XC 10.6.8 and iPhoto  8.1.2 and later  or iPhoto Library Manager 3 (for OS X 10.5.8 and iPhoto 7.1.5 and earlier) and launch.
Click on the Add Library button, navigate to your Home/Pictures folder and select your iPhoto Library folder.
Now that the library is listed in the left hand pane of iPLM, click on your library and go to the File ➙ Rebuild Library menu (iPLM 3) or Library ➙ Rebuild Library menu (iPLM 4) option.
In the next  window name the new library and select the location you want it to be placed.
Click on the Create button.
Note: This creates a new library based on the LIbraryData.xml file in the library and will recover Events, Albums, keywords, titles and comments but not books, calendars or slideshows. The original library will be left untouched for further attempts at fixing the problem or in case the rebuilt library is not satisfactory.
OT