Help me figure out why my Indesign CS5 keeps crashing

Question

Here's the scoop:
I created a long document (book) in CS5. I'm a novice so it was a miracle. lol.
I needed help with the Index, so sent it to a gal with CS4 to create the Index
She sent it back. I put it into my Indesign fine...but I then started noticing crashing if I was correcting anything, such as deleting several lines, inserting page break, doing the 4th bullet, doing the 4th of a correction, trying to move a section, changing the font size of a heading, etc. Constant crashes.
My Crash Report: http://pastebin.com/TT9Kr45e
I even tried making a copy to start deleting half, then delete half of that...etc...to find the problem. It only caused another crash. This was when the original doc was now next to the Copy. i.e. Indesign couldn't handle both at all.
I'm stymied! HELP.

Answer 1

It's completely updated. Was before this all started.  Here are all the facts as I know them about the crashing. Hope someone can come up with an idea.
1) Sent my CS5 to someone in the IDML because she has CS4. She did the Index for me, and sent back to me. Crashing starts. Index issue??? If so, what??
2) Crashing occurs when I'm trying to make changes in text: when I press delete at the top of the page (to bring back page which pushed over to next page), when I try to delete a section, changing the font of a heading, doing the 4th bullet of four items (first three bullets were fine; fourth one crashes me), doing a full return to add a space (very common reason for crashing), etc.
3)  I have been unable to make another CDML–it stops about 45 pages from the end on "Graph 50″. I looked at my errors–found a huge body in inset on the page right about Graph 50 that I didn't need. Got rid of the inset. Could the crashing be from something in Graph 50 alone?
4) Trying to do Split Story crashes Indesign
5) Crash report–does it have something to do with the "library"??? If so, how do I find this?
0   libsystem_c.dylib                  0×92521b4a memmove$VARIANT$sse42 + 397
1   PublicLib.dylib                    0×01303e87 CTextAttributeSuite::ChangeParagraphDirection(ICompositionStyle::ParagraphDirection) + 20359
2   PublicLib.dylib                    0×01161a19 UIDList::Append(IDType<UID_tag>) + 57
3   com.adobe.InDesign.AppFramework     0×0b9321db 0xb910000 + 139739
4   com.adobe.InDesign.Generic Page Item     0×115119df GetPlugIn + 1416831
5   com.adobe.InDesign.AppFramework     0×0ba2348a GetPlugIn + 976634
6   com.adobe.InDesign.AppFramework     0×0ba236c3 GetPlugIn + 977203
7   com.adobe.InDesign.Layout          0×11b16a34 GetPlugIn + 17220