Hi Warwick, so sorry to hear it's become worse, but opening up to your doctor, and now especially to your DH is a good thing.
Please don't feel like you're on your own in this, you mentioned thinking that at 56 you thought you would be through the worst, just to say that I am 54 and over 4 years without a period but this terrible anxiety is one of the newer symptoms - I too thought I'd be through the worst by now.
I had a particularly bad few days a couple of weeks ago, and I really thought I was on the edge of a breakdown, I still have the anxiety of course, but that feeling of hanging off a dark abyss by my fingertips has subsided for now. Yours will too, we will get through this. I know ADs don't agree with you, but what about a beta blocker or something stronger for those really bad times? I have beta blockers now to use 'as required' rather than daily, haven't taken one yet, but it helps to know they're there.
Hang on in there Warwick xx