I’ve had IC for decades, one of the symptoms of which, as you have noted, is urinary retention. I had multiple hydrodistensions with limited relief. For the last couple of years, my symptoms improved in that I did not have the urgency, frequency, and pain during the day, but I did have nocturia which has severely compromised my sleep. Six months ago I had a urodynamics test after which my bladder suddenly stopped working entirely and I have had to use intermittent self catheterization since then. The urologist has no diagnosis, but my theory is that it’s likely muscle damage. I am presently undergoing PTNS therapy, but I am not optimistic as to whether that will deliver relief. I don’t know whether this helps or not, but I can certainly sympathize with your situation.