Learning to pass a driving test - UK

I'm 56 next week. I can drive... or at least I could 20 years ago, but I never passed the driving test.
I could do it all during lessons and practice, and my instructor would keep telling me I'd have no problems passing a test.

I failed - TWICE!

The first one, my driving examiner had one of his seniors in the car sat behind us - he was sweating more than I. Needless to say that made me more nervous that I already was. Afterwards, after my fail note was duly handed to me, my instructor said I could have refused the examiners' tester and that the examiner would have been extra harsh on me as he was under the eagle eye of the bureaucrat. If only I'd known. I still may not have passed but I will never know.

The second one I took around 6 years later (money factors prevented an early re-run). Refresher lessons, new instructor, same old same old about how competent a driver I was. I wondered then if it was not just pat-talk to keep me paying.
Second test date was sent for and received - and from that moment, with no real necessity, I panicked, and panicked and panicked. The day of the test came and the practice lesson beforehand, I stalled the car for the first time EVER. I rolled back on a hill start which I had nailed on the first attempt all those years ago. I screwed up my reverse round a corner... this wasn't going well at all. All I could hear was my own heart beating.
Needless to say, I failed the test. I was a physical wreck, which was odd considering I'd done it before with a lot less stress. Perhaps it meant more at that time. I just wasn't in a good place maybe?
I took a few more lessons 20 years ago this month, but finances or lack of made me quit again.

Now it's seriously getting to be a pain not having my own get around freedom. It didn't matter in the city - there's always transport. It mattered a bit when I moved to a coastal town, but some adjustments and I could still get about.
Now I live in a small, rural town with one bus route and at least 5 miles to a train station. I have my pushbike, but I can hardly take my 2 dogs to the marshes, or pop to the coast 25 miles away with that.

So, I've started to relearn driving, only nowadays you have to pass a theory and hazard perception test too, before anything else. Theory - great - I sail through the practices.

Practical, great, I can still drive although a little rusty, I'll soon polish up.
Hazard perception - now THAT is my downfall. It's not that I can't spot hazards when driving - I can't spot them quickly enough looking at a tiny box on the computer screen. In a car you get more vision, more vista, more all round awareness. On a screen you get a tunnel vision shot and one chance to click at 'just the right second'. I can do it - just. But I'm nervous already that on the day of the real thing I'll be so nervous I can't make these on screen judgement calls...

Am I doomed to rely on others to get me around?

I'll just have to keep on practising.

Tips and advice welcome.