The only time a T went went with me physically was 30 years ago but it helped tremendously. Other times a T has arranged to call the Pdoc before or during a meeting to help articulate and tell the Pdoc about observed behaviors. I like it when the T and Pdoc have open communication. even though anger and irrational thinking are part of BP I have a hard time admitting to those. It's easy to avoid talking about things and presenting myself in a high functioning way since most Pdoc appointments are short.
Take her up on her offer.