I do feel for you!
I didn't learn to drive until I was 28!
You are at and added disadvantage in Colchester because the road system there is a nightmare!! Here is my suggestion... when I started learning, I spent weeks just driving nowhere, all around the quiet rds in the evening, lots of residential estates with very little other traffic. I used to get so upset by other peoples behaviour to me as a learner, and then I just kind of realised it was them with the issues, not me!
If people are being arses pull over, let them pass! But if you are building up to things slowly you will never be on a road you cannot handle! Try heading to Layer Rd area, there are loads of residential rds, they are wide and most quiet!
(Hubby and I went to music college in Colchester in the 90's)
I passed my test in the September before I turned 29, first time, with not even a minor fault!

Believe me, when you hold that certificate in your hand, it is SO worth it!