I suspect that you, like me, have an underlying cause for raised insulin resistance. In my case that is a prolactinoma, PCOS and obesity (all connected, and all very unlikely to ever resolve themselves).
Your reasons may well be different from mine. There are many reasons out there, from thyroid problems, to genetics, to environmental factors.
I can certainly beat my insulin resistance downwards with extended fasting and exercise (it hovers in the 'normal' HOMO-R range but is significantly higher than 1.0), but no matter what I do it bobs back up like a cork in a bottle as soon as those activities end, or I eat even 5-10g of carbs. So I take the view that while I do my best, and I keep to a sustained very low carb way of eating, and I do some dog walking/pilates type exercise every day, I am not going to flog myself with sustained fasting or sustained exercise. I just accept that it is what it is, and life (and hyperinsulinaemia) is still significantly better than it used to be before I introduced the changes I have.