I've had similar trouble with diabetes nurses and consultants. HbA1c too low, must be having loads of hypos, "ooh that could be dangerous", "we don't advise that", "you should do this/that" etc.
I'm well read, careful by nature and stubborn when I'm confident I'm right.
Now that I've seen my current DSN and consultant each more than a few times, they've had a chance to get to know me and they've seen the results of two different CGM trials in the last year, they've accepted that:
a) I have only occasional hypos which are quickly spotted and treated
b) I have strong control -which accounts for how I achieve an HbA1c under 6%
Keep doing what you're doing britincali. Don't let them bully you but aim to keep them on your side. Show you're listening to them even if their views go against your own experience. I find the line "I'll bear this in mind/take this into account" works quite well to show I've listened without committing to necessarily change.
Despite the first few visits, which were enough to induce paranoia much the same as you described it, I have since found it easier to have a two way discussion now and my clinic visits are starting to become a good way to see things from a different view, which is actually quite useful. Both my consultant and DSN are very supportive deep down so, even if I still don't totally agree with them, I regard myself as lucky to have them as part of my health team.
So, in summary, give things time, don't let paranoia take too much grip and try keep the communication with the DSN on track even if you don't agree with what's being said. You're not obliged to do what they say and if you're doing things safely (which it sounds like you are) it'll only be a matter of time before they start to trust you.
Ed