Eating Disorder. Intake via therapy?

I am a 32 year old woman. I have been overweight since my childhood. In fact, I have never seen my normal size body and face. I currently weigh 95 kilos which fluctuates between 92 kgs to 97 kgs. It has been the same for the last 10-15 years. I have tried several diets and exercises but I lose interest after losing 2-3 kilos and then discontinue. I don't eat a lot of junk food but my meals are of large quantities which I have tried to reduce. The problem is when it is something tasty I tend to overeat to the point of stomach ache. I pop in an antacid and after some time, I feel okay. This has been going for many years now. Someone told me that I have an eating disorder and asked me to take help from a therapist. Can someone please explain if it is possible to reduce my food intake via therapy ?