Hello and welcome,
I agree that there is no point in blaming yourself. I too went on many low calorie diets without much success unless I did an insane amount of exercise. I have lost weight going low carb.
There feels like a lot to learn at the beginning. You will get your head around it and there are many people on this site who are helpful.
As a fellow emotional eater I agree with
@TriciaWs - lots of great ideas there. I have diet jelly- usually with a bit of double cream which them makes it a bit more filling.
I would ask your doctor for a change to try to manage the diabetes on either just diet or diet and metformin (and while you are at it ask for the slow release version of metformin as more people seem to tolerate that without symptoms.
Good luck and welcome.