I was the same. I passed the other day. Mid 30s, years of lessons, 3 different instructors, 2 different test centres.
For me, it was finding the right instructor. I didn't realise the first 2 were just not compatible with me. The third one recognised:
I'm a perfectionist
I'm an overthinker
I'm a nervous driver
And tailored the lessons to get me confident with it. 20 hours with him was better than the previous 50 hours combined. It was the key to everything.
Now I'm on the other side, I would ask the instructor exactly how many 30+ year olds they have taught, how they'd suggest helping an overthinker etc. I'd listen to their answers like a job interview because 30 year olds and teenagers can't be taught in the same way.
17 year olds are learning new skills daily, don't have to worry about the same shit we do daily... do I have enough milk at home, will the commute be a nightmare tomorrow, are the kids OK at school, did I leave the oven on, whatever. They also don't have the same sense of mortality quite frankly. Often they aren't paying either! Another stress.
An instructor needs to approach teaching you differently and I sooo get that now thanks to mine.
If you live in Kent, PM me for my instructor!!
Best of luck. Still with a manual too, I'd say.