Hi,
I am a type 2 diagnosed in 2005.
Way back in 2014 I was going through what you appear to be going through with Insulin Resistance and just kept getting told to up my dosage, my sugars were regularly over 30.0 at the time and my GP kept saying to me that when my meter said Hi it wasn't being friendly and I should really go to A&E, but I said it wasn't practical for me to go to A & E on a daily basis!
The local specialist Diabetic Team were as much use as a chocolate fire guard with one doctor having a go at me for failing to keep a single outpatient appointment when I was lying in a hospital bed at the time! I had phoned the clinic to let them know why I couldn't attend but he said that was not good enough! If he couldn't listen to me about that you can imagine how much he listened to me about my insulin.
The nurse at my practice said there must be something else going on (she thought it may be linked to me also having ME/CFS), and said if it was down to her which sadly it wasn't, she would have me into hospital and take me off all my diabetic meds and gradually try to reintroduce or try new things to see what worked and what didn't. I trusted her judgement.
Anyway naughtily I went home and went cold turkey and took myself off all the insulin and monitored and documented my blood sugars carefully for two weeks - it had little or no effect on my sugars in fact if anything they slightly improved without the insulin! I went back to my doctor armed with the results, they obviously did not approve of what I had done but I had at least proved my point that the insulin was having no effect and they finally listened to me.
My GP and Practice Nurse hunted round and came up with what at the time was a new tablet - Forxiga /Dapagliflozin and this changed things significantly for me. I started taking that combined with maximum Metformin and maximum Gliclazide, and my sugars finally started to come down and settled around the 15 - 20 mark. Over the following years with a concentrated effort on my diet as well I now have them down to the 10 - 15 mark still to high but so much better than they were. I can still get hypo like symptoms if it drops to 7.0 or below which mainly happens if I am in hospital, because again they do not understand my circumstances and without small but regular food intake my sugars can plummet with the resultant effect.
It has taken a long time but my GP is finally really pleased with my latest HBA1C results and the Community Team have just discharged me back to GP care, sadly a lot of damage has been done with having such high sugars for so long, particularly to my eyes, and the painful neuropathy in my feet.
I wouldn't suggest you try anything so drastic but do recommend you keep persevering with talking to your medical team, as sometimes doctors/nurses can get so stuck with following the 'normal procedures' they forget we are individuals and our bodies can react differently to the standard treatments especially depending on what other medical conditions/medications we have at the same time.
Good luck and I hope this gives you some encouragement that even if it does take years hopefully you will get somewhere eventually.