[Uptown Girl]

Hi Bare-
I faced the same situation. The options aren't great.
There are a few products (I found online) that can help blend the demarcation line, but they are temporary cosmetics- and wash off. One is like a mascara wand- basically for around your face/hairline- one is a shaker of colored fibers- more for the top of your head. If you follow it with a shot of hairspray, it stays put.
I used these when I was still working and had to be in the public eye. It was a pain, but got me through for a time.

When bopping around casually, I wore a low ponytail and a baseball hat.
I wanted to get a wig, but friends and family talked me out of it.

Eventually, I decided to cut my hair into a pixie to get rid of the majority of color. My hair was originally below my shoulders. The pixie was a shock- to myself and to others- and I still had to deal with dark tips, which now looked awful. No way to camouflage the ends.
It took well over a year before I liked my hair again. My hair is now silver-white and I have embraced the look. My husband says he likes it a lot. (My avatar is how I USED to look- a hundred years ago!)


In retrospect- I would get a great looking wig while transitioning to your new natural color. Better yet, I'd get two, to always have a fresh one handy. And I'd keep it my secret.