I understand that you are looking for a psychologist who specializes in addressing PTSD in someone who also suffers from bipolar disorder. There are a number of psychologist directories you can try, including American Psychological Association Help Center, Association for Behavioral and Cognitive Therapies (ABCT), and Network Therapy, to name just a few. A search on the web for therapist or psychologist will turn up many directories. You or your boyfriend may want to call a few on the list and interview them, explaining your situation and asking about their experience with PTSD and Bipolar Disorder.