Oh honey, poor you, i had all this with my beautiful Pepper a few weeks ago, i had to make the decision because he needed the op again after a few weeks after having his first (huge) stone removed, for the last 6 or 7 weeks of his life he sqeaked everytime he peed

It was really really distressing for me, having said that, like yours Pepper was completely eating, happy, running round etc, but i decided not to put him through the op again for four reasons:
a/ if it happened so soon after the first op, he would surely keep needing the op
b/ he had lost so much weight i didnt think he would survive it anyway
c/ he had been messed about with so much, and taken that many meds, and;
d/ on his last day, at 3.45am his bladder was completely full and nothing was coming out and he was in agony, i couldnt bear for this to happen again one day when i was at work and for him to suffer all day long
hence, PTS

8... :0................ i am happy with my decision now but i miss him soooo much

I hope any of this helps you with your situation.
You have done so well with him, and i have followed your post, i am sorry it may have come to this for you (hugs)
