You're welcome here, Clown. There is a lot of overlap between the two disorders. I know they share extreme mood swings. I don't know as much about bipolar, but I know it can be treated with medication, whereas borderline cannot. People with BP can have seasons between episodes where they are stable, and only have hair trigger responses during an episode, where pwBPD have hair trigger responses most of the time.
I've found the tools useful in all of my relationships. More than anything, it's helped to know that I'm not alone, there are others out there that love these brilliant, witty, sometimes difficult people and are having to find ways to cope.
Have you asked to talk to the psychiatrist? I think that's pretty reasonable. If that doesn't pan out for whatever reason, are you open to looking for a therapist for you? Counseling has always made me feel supported.