@LQFP64 Take a deep breath.
Now take another one.
Now ask yourself: “what was my purpose in starting this thread”?
A. For sympathy and commiseration
B. For practical advice on how to resolve a very thorny problem.
If it is A, you need to say so at the start of the thread, rather than write
If it is B, you need to understand that you may not like the advice that you will get. You also need to understand that nobody here is “taking the side of UCSD”.
What people are doing is pointing out the issues with which you need to deal, in order to get a resolution that will help you.
When people write that the you haven’t followed the written university policies, they are not “taking the university’s side”. They are pointing out the central issue with which you will need to deal. If the university has a written policy, it doesn’t matter that the policy seems unfair, they (the university) still will follow it by default.
What people are trying to tell you is that, you should not try and deal with your issue by claiming that “it is unfair”, because that argument will generally not convince the university to reverse the written policy in your specific case.
What people are telling you that you should do is either ask the university for an exception to their written policy, and put together a strong argument as to why the university should do so, or hire a lawyer, and let them argue your case.
People also gave you good advice as to what to do if the university refuses to change your grade, how to proceed with you grad school plans. Since there is a distinct chance that the university will reject your request, this advice is very useful.
Getting annoyed or angry at people offering good advice is not the best way to proceed in life, if you want to be successful. You thank them, and decide for yourself whether to follow their advice. You don’t speak angrily to them (IRL), or express anger in writing (online).
Good luck with whatever you do.