I am sorry to hear of your troubles at school, it must be taking its toll...
The thing that stands out for me and that is obviously making you stand out to your peers is the fact you are in and out of hospital and off school all the time.....
realistically this can be avoided, but its not your fault.....you should be getting support and education on how to manage your blood sugar......
are you or have you had this support?
could you elaborate on the diabetes specific bullying? what kind of things do they say....? If you don't mind of course...