I’m part of a program set up by the ASPCA called (I think) Capture, Neuter/Spay, Release. I took home two ferals (with microchips and rabie shots), a tiny shelter, and freed them in my backyard. I feed and water them everyday. One is less afraid of me but the other is a real tiger! She resents having to take food from me and turns over her water bowl every night with real violence. But she still comes and eats...
You are a good woman. I have to take my food up at night cause of the coons and possums but sometimes I forget and they turn the bowls over and such. It might be the coons in your neighborhood turning the water over.