Struggling with Eating Habits and Seeking Advice

For most years of my life, I have struggled with the textures of foods and have been labeled a 'picky eater' my entire life. As a kid, all I would eat was Pringles or Goldfish for every meal because my parents were not the greatest at enforcing things. When I was around probably 8 or 9, I went to therapy for my eating habits and it did not do anything simply because my therapist and I just played board games the entire time. He barely helped me at all. Now, I am rarely eating at all and my eating problems are stronger than ever. When I eat, I never finish my food and sometimes I hide it in my mouth just to go and spit it out later. Stuff I used to eat religiously and say was the best food I have ever ate now upsets my body and I feel a huge discomfort or pain after I eat. I am now usually eating only one meal a day unless if I am at my father's house—for clarification, my parents are divorced—because when I am there, I am forced to eat all three meals. I have a doctors appointment on Friday and I want to bring this all up with my doctor, including some other things going on in my life (for example, how I need a therapist, may have vitiligo like my father, etc.). Would anyone have any sort of advice on how I can try and make progress and heal? And any advice on how to tell my doctor would be fantastic.