I've been diagnosed with bipolar, but my new therapist thinks I might have borderline instead. I feel like I can relate to both disorders. I wonder if the bipolar symptoms were traumatic enough to trigger the BPD symptoms (I had my first psychotic depression at 12; that kind of thing would mess up development for sure) or if the BPD symptoms made me more vulnerable to developing a mood disorder (I remember being very emotionally sensitive my entire life).
I don't know if I have bipolar, BPD, both, or neither. All I know is that my brain works differently, and that that is both a blessing and a curse.