Fix her diet
My wife's a type one diabetic
Saying she's insulin resistant is like saying I'm tired so I must be sleep resistant.
If she's type 2 then fix her diet and keep up on meds and slowly introduce her to excerise and weight training. Don't jump all in the first day till you know how her body will deal with her glucose levels. Nothing is scarier for my wife and I than when her glucose levels suddenly drop at the gym she carries emergency Apple juice whenever we go, but she's pretty anal a lot checking her glucose levels. She has an inslulin pump. Again she's a type one diabetic has been since age 6.
I'd suggest reading up on fixing her diet and get off on a low carb diet if it's just insulin resistantance