Yes these two illnesses can be comorbid. I have been living with Bipolar type II and Borderline Personality Disorder since 1996. I am currently on Lithium and have been taking this med since 2003. It seems to be helping some days, others I'm not as sure. I struggle with depression most of the time now, but I do still have mood swings. Unfortunately, BPD compounds the issues that arise from Bipolar by causing severe emotional cycles throughout the day. In addition to the medication I take, I also participate in individual counseling and DBT (Dialectical behavior therapy) to learn to regulate the symptoms associated with BPD. My goal is to have stability in my life and each day I do my best to work toward that goal. This seems to be one of the most difficult journeys I've ever attempted. I have struggled with relationships with friends and family. I have struggled with employment. I have struggled in almost every aspect of my life. Most days I try to keep my life as boring as possible, avoiding the drama and crisis's that seem to accompany bipolar and BPD. You have a tough road ahead of you, but if you keep the goal in mind and work hard, anything is possible.
Hope this is helpful,
J Lodge HR Support