I'm diagnosed with both Bipolar Disorder and Aspergers and have been for a few years now. I was diagnosed with Aspergers at 16 (a late diagnoses indeed) and Bipolar at 18 during an inpatient stay. It definitely adds a layer of complexity and then some, mainly in the area of treatment. Therapy is very difficult for me and I can't talk easily about how I'm feeling; an inability to express my emotions and thoughts normally leads me to punching myself and walls because of the frustration it causes.

DBT was actually not offered to me for a while because my psychiatrist and therapist knew that I'd find it difficult and the ASD would be a barrier of communication in speaking therapies. My poor social function also certainly presented me and my therapist with issues during the group sessions.

The diagnoses should help with your treatment plan - that is, you should be provided with extra support and different treatment methods to work around the ASD.

As for comorbidity between the two, it's not exactly common but nowhere near rare for Aspergers and Bipolar to be found together. In fact, I remember reading about it in a National Autistic Society (UK charity) booklet. Mental illnesses in general are definitely common in those with an ASD.