I'm sorry to hear about what you went through- I get that one single dentist can make every dentist terrifying.
I'm not sure if your GP can refer you to a public dental hospital, this is something you probably need to ask your GP. From my own experience there was a significant wait (I had wisdom teeth extraction), but it could be different where you live. If you do have private health this could also be an option as well.
I suppose the only thing that I could suggest is to find a dentist and see if you can just have a 'consult'. This way you're under no obligation to do anything (or even open your mouth!), and you can see if the dentist is right for you and someone that you could feel comfortable with.
Hopefully this helps a little. If you're able to search 'dental' in the search bar you should hopefully find other people who can relate.