My spouse and I were married in Sept. 2007 in Texas, she entered on a K1 visa. In July 2008 we received her condional green card. Now during this time she went to work as a nanny for a family in California. She had opened a bank account in California and now has a drivers license there. Since being married she has lived longer in California then here. There has been no abuse, there are no combined assets, no comingiling of funds and no children. She will need to apply for adjustment of status in March 2010.
What will happen to her case if we divorce? What will happen should she return and start living together and create a family together? If she doesn't return prior to the adjustment deadline should I notify USCIS about a potential divorce?

Sorry but it's obvious that you're being used. Here's the deal:

She must file (jointly) removal of condition after 2 years, if she fails to do so, with no domestic violence/abuse prior to the separation/divorce, her legal status will be revoked.

What you should do is filing for a divorce or annulment, then inform USCIS in writing about your status and request to withdraw sponsorship. Don't expect she will be back...