Sorry to hear you've been experiencing similar problems.
I had a cystoscopy (not recommended!!), physical prostate examination and massage, ultrasound scan and numerous blood tests, none of which showed any obvious problems.
Until recently, the Sativex was making things tolerable and, as there do not seem to be any confirmed treatments for non-bacterial prostatitis, I was "putting up with it" (the way I do with my PPMS!).
However, as things have got so much worse and there is doubt regarding the prostate origin, I have persuaded my GP to explore other avenues ie the MS/Bladder issues.
PS Have enjoyed your posts over on the CCSVI forum