The diagnosis was sort of slid under the door on me....and then slapped on me....and then just looked at calmly with me.....

So, I didn't get to tell anyone anything.....But, what I did make sure I did, as we were doing the meds adjusting thing, was make sure that I remembered to tell them all my symptoms, and I saw my psychiatrist every week for about two months, then every four weeks, and we've been at every 4-6 weeks since then, for years and years now. We change. A good psychiatrist knows that. So, one way to bring up the borderline questions would be to say, "I've been experiencing x..y..z..at such high levels it makes me feel like I'm a borderline. Do you think that could be true?"
Seems reasonable to me....Start with your symptoms and lead up to the question.