This patient support community is for questions related to juvenile diabetes including celiac disease, depression, diabetic complications, hyperglycemia / diabetic keto-acidosis, hypoglycemia, islet cell transplantation, nutritional issues, parenting a diabetic child, pregnancy, pump therapy, school issues, and teens with diabetes.
First I want to thank you for your work and your going these extra miles to figure out what's right for this youngster. I'm not a physician, but a long-time diabetic.
From what you've written, my best guess is that he acts out quite simply because "My parents don't care." His words and your experience seems to indicate that that's at least partly true.
As I'm sure you've seen, kids with or without health issues YEARN for parental attention and if they don't get it on a regular basis for normal kid-life things, they can escalate bad behaviors in search of it.
There do seem to be plenty of parents too busy
In my opinion, diabetes complicates behavior issues, but it doesn't cause the things you describe.