Diabetes Type II: You can lose your feet. You can go blind. The risk of cancer, stroke, and heart disease go way up. You can get kidney failure. There's more, but it's a long list of shit that can go wrong. You don't want it.
Diabetes type 2 is no joke and will change yoyr life for the even worse than it right now. Don't waste your life like this even if you have a shitty situation.
If you have abusive parrents try to seek help from the police or other insurances.
You need to get the fuck out of there, there's more to life than being suffocated by your parents. Don't let them have the last laugh, the biggest fuck you you can give them is to escape their obvious need for control.
I can't pretend like that's easy or that I would know how, but you've got to explore everything you can possibly do to be removed from that situation. By your description it sounds like they're doing things that are likely legally abusive. If you can get out of there just imagine how much better your life can be out from under their thumb.
Both my younger brother and I got diagnosed with Type 2 diabetes. I was diagnosed 19 years ago. I modified my diet, started getting a lot more exercise, and religiously took my oral meds when I started having to take them after a few years. I check my blood sugar often. My diabetes is still well-controlled. I had a bout of frozen shoulder a few years ago (that got corrected with surgery) but other than that I'm fine at age 51.
My younger brother got diagnosed about ten years ago. He did nothing to change his diet (which remained awful) and stayed obese. He continued to smoke heavily and made no attempt to quit. He never even tried to get any kind of exercise. He was prescribed diabetes meds but I don't know how good he was at taking them. Eventually he lost a big toe, and then slowly lost kidney function which eventually required him to get dialysis. He suffered two heart attacks on two separate occasions (interestingly, both attacks occurred during dialysis sessions). The second heart attack killed him. He was 47 years old.
So, that's what can happen if you don't get treatment.
Work on getting yourself out of that living situation. It'll be a lot quicker than giving yourself diabetes to punish them.
Hiding your meds, unless the intention is to prevent you overdosing on them, is not OK. Do you have any family or friends you can ask to intervene with them? Your doctor, maybe?
Get out for a walk. Twenty minutes first thing every day will help, even if you don't really want it to right now.