So sorry to read this, Tari. I believe that losing a once trusted and relied on dentist is one of the hardest and most scary things when beating dental fear and it would make me feel despair as well.
You are mentioning that letting someone new look in your mouth is a horrendous thought, so what about just having a look around at practices in your area and see if there is one you feel you might want to give a try? Maybe getting in touch and let them know about your situation?
If your previous dentist has someone who took her place and you feel you might want to give them a chance, maybe a short consult or a call would be a good start?
I know this is hard. On the other hand if you managed to find a new dentist once, I am sure you will be able to get there again. It's not the nicest thing to experience as a nervous patient, but you can get there on your own pace. Having managed to work with a dentist in your past might have help you to know more about your fears and what could help which makes things easier for you in the future.
All the best wishes and let us know your thoughts