Just failed my test for the second time today 
I was behind another learner driver also in an instructor's car. They dithered for a moment, then indicated left as if they were going to park but also started to roll back [no reverse lights] so I was not sure if they were parking, about to continue on or were about to attempt a three point turn.
So I stopped for a couple of moments and the traffic stopped behind me. However when I saw that the car was finally pulling in to the kerb I said to the tester that I would now go around them as they were obviously parking.
Nothing was said by the tester at the time but she failed me on this. She said that I should have kept going and gone around the parking car. By stopping I had caused the cars behind to stop and this was basically not acceptable.
So this is a serious fault 
I am just so annoyed as the rest of the test went well and I only got 3 minors in total. I did the bloody bay park perfectly as well. Even my instructor was gobsmacked that I failed on this point. My instructor said that i would also have failed if i had kept going and the car in front had decided not to park [and imo it really wasn't clear what they were planning to do initially].
Am I being unreasonable in feeling that driving tests in London are unreasonably difficult or should I just suck it up and get over myself.
The irony is I actually have a driving licence from my country of origin and have driven for a number of years there so am not a complete newbie. I did lessons to get myself ready for the test here and my instructor has said that I should pass so why the hell do I keep failing 
Any stories of either test rage or woe will be gratefully appreciated as I am feeling a bit crap at the moment and really wondering if it is worth my time and money continuing.