I definitely think you are in the line of a double whammy, Annette. Yes, extremely high blood sugars can(physically) affect mood, but you also, as you say, are "very irritated and sad about your struggle with diabetes". You don't say too much about what your efforts to control your blood sugar are like but you have not been doing well for awhile and that has got to be depressing and frightening especially for a young woman who has her whole life spread before her and wonders what it will be like.
My suggestion? Put all your effort into seeing what you can do to get your blood sugars down. That will make you feel better physically (including the mood changes from highs) and emotionally, because even if it takes awhile to see the results, just "doing something"can make us feel more in control and more hopeful. Do tell us what you need and talk more about your challenges so we can help. I recommend if you don't already have it that you get Using Insulin and Pumping Insulin by John Walsh. The first one helps with things like basals, I:C ratios, Correction Factors, carb counting, etc. The second one helps you use your pump to the best advantage. Many people believe a pump helps lower blood sugar, but if it isn't programmed right and you don't utilize the basic skills of adjusting doses and numbers, it can't do it for you. You've taken the first step by posting here. I think many people who were diagnosed as children tend to go through a period of not dealing well with their Diabetes but you CAN get back on track!