What you are describing is the high you get from the spike in your blood Sugar followed by a low when you are feeling lethargic. Do you also suffer from depression? brain fog?
Can you give me your daily menu? What kinds of foods do they serve at the cafeteria? What do you eat there?
I know its hard when you are in this cycle. Its hard even to know what to do first. Sometimes we try certain things but when we fail we feel worse and with a sense of helplessness. I can help you out if you like with what I know and have experienced for myself. I have been in a similar position as you. I was (am) pre-diabetic.