Great advice, Seesaw.

The pausing/breathing thing I do is just stalling for my own brain sake. The disordered people I've been involved with tend to have kept things unbalanced with a sense of pushing and urgency. By stopping for a moment, it allows time to actually think about what was said, rather than responding to an old script out of habit. The pause might also give you a little more sense of control over the situation, since it gives you some control of the pace.

And I agree wholeheartedly with seesaw's other post about staying on topic. Disordered people are so good at shifting focus that they seem to do it compulsively, and even when it's unnecessary. Maybe it could help to think of or even write down, a mission statement when it comes to what needs to be accomplished in regards to a given topic or time frame? Then stay on target. Don't get down in the weeds. If she tries to shift the topic, you bring it right back to the one that matters. This might take a little practice, but it can help you feel like you're in the driver's seat, and could also remove some of that pointless white noise that may be keeping you feeling cloudy and off balance around her.

Oh, and make sure you get enough rest. An exhausted mind is one that isn't fast or clear.