But the problem remains this: It is still causing me massive pain, which I believe is really a manifestation of post traumatic stress disorder. I am absolutely terrified of going to see a mental healthcare provider.
It definitely seems like you're suffering from post traumatic stress due to the way people treated you when you were younger. Given your past experiences and the difficulty convincing a mental health provider that other mental health providers caused your post traumatic stress, you may be better off treating yourself using self-help books written by mental healthcare providers such as this one: The PTSD Workbook: Simple, Effective Techniques for Overcoming Traumatic Stress Symptoms: Williams PhD LCSW CTS, Mary Beth, Poijula PhD, Soili: 9781626253704: Amazon.com: Books