... each time I try the test remembers and gets even harder ...
It does get harder, but not for the reasons you suspect. The test is "Adaptive", meaning that it changes its difficulty level to match your knowledge level. Since you (presumably) have more knowledge than you did when you first took the test, you will see harder questions.
It works much like the Divide-and-Conquer troubleshooting technique, in which one looks from the middle to determine if the problem is to the left or the right. An adaptive tests start by asking you a question. If you answer wrong, it then asks easier questions. If you answer correctly, it asks harder questions. In the end, you end up answering questions of a particular difficulty level with about 50% of your answers being correct. If this final difficulty level is "good enough", you pass.
The thing that makes this stressful is that we are trained to judge how well we are doing based on how many questions we answer correctly. With adaptive tests, everyone ends up answering incorrectly, so everyone feels like they are doing poorly. The difference being that those who deserve to pass are incorrectly answering much more difficult questions.
In your case, the fact that you are seeing more difficult questions is a sign that you are getting closer to passing.
Thanks for sharing your experience. I'm sorry that this journey's been this much of a burden on you. It shouldn't be. As far as tips, the only thing I can tell you would be no different than what I'd said already throughout this forum. In addition, I hear that the test changes often. Add that to the fact that the test is digital, who knows how many actual questions there are, and where they're coming from, or how they're pulling them out to give you on your exam. Taking that exam nowadays is anyone's guess as to how to actually prepare. From the feedback I am hearing, it doesn't seem to be any different from the time I took it almost a year ago. Will ISC2 do something about it, it's anyone's guess. They have to know the statistics though on pass/fail.
I can totally relate to this post. I just failed the CISSP exam a week ago and felt like I could have written your post. Within the first 5 minutes I knew I was not going to pass the exam because of the way the questions were worded. I actually thought that I had been give the wrong exam because the questions were so foreign. Nothing like what I had studied. I felt like I had wasted all those hours of study and all those hours taking practice exams. It would be nice if the CISSP were really a test of our knowledge of the material and not a test in the mastery of exam-taking (i.e. ridiculously ambiguous worded questions).
@jrags51 wrote:... three instructors ...written by eight different people
The test itself was written by hundreds of CISSPs that came before you, so it is a good thing that your training materials similarly have many different authors.
...if they got it wrong in the book, you need to drink the Green Cool-Aide and answer the question WRONG....
(ISC)² test writers and educational staff do not talk to each other. This is a requirement of ISO/IEC 17024, the "certification standard" to which (ISC)² complies.
Instead of proclaiming "they got it wrong", instead ask yourself "how could that be"? Checking against the errata and taking a "deep dive" into the topic with other books and reference materials (e.g. NIST and ISO standards) will oftentimes identify the subtle differences that make it possible for seemingly different views to not be contradictory. I also suggest reading this discussion, not so much for @rslade's excellent questions, but more for the analysis of the answers and the related chatter.