In spite of everything, I cast my vote amongst the other early voters in my town. I had a weekend to drive from the clinic back to where I live, so I looked up the early-voting schedule for this year's election which schedule can be referenced on the Internet. Turned out that early-voting hours had been arranged for Saturday afternoon and Sunday morning!
So I showed up at Town Hall, duly face-masked, and there was a policeman on duty by the voting booths. I filled out my ballot and signed the official envelope, and I was done. Then headed back to the clinic, which feels more and more, these days, like my home, than my apartment does.