Hello,
I can understand where you are coming from because I had those thoughts when I first left JWs (20 years ago)
It is all to do with mind control and been told over and over that they are right.
You have to study the Bible, research to come to the conclusion your self that they are not right.
I have family member who left JWs 30 years ago and recently went back. You see it was because she never really left them. In her mind she thought that they were right she was wrong in not wanting to follow their teachings any more. After so long she has now gone back. How so sad.
You have to leave them mentally, emotionally, spiritually as well as physically.