Your girlfriend is the person who decides when she can no longer work. Having said that, it's best to have some doctors lined up who agree with her. Any documentation medical or non-medical needs to be submitted with the application in order to have the best chance at winning. Start with family and co-workers who can write letters affirming her ph ysical and mental limitations in doing her job.
I assume by PD you mean personality disorder. If so there are a number of supplementary forms used for mental disorder. Check out http://ssdi-help.com/ssaforms/ssa-forms.htm which has copies of the Psychiatric Review and Mental Residual Functional Capacity Report. These are supplemental forms her doctors can complete. Also, personalily disorders are specific listing in the SSA's Bluebook which lists all the criteria for immediate approval, http://www.ssa.gov/disability/profes...ltListings.htm
PD is 12.08 in the Blue Book.
Also, if she can complete the Adult Function Reprot (also on the SSDI-help website) with thorough answers, it will help her case.
Good luck.
Trudi