You're right to be concerned about your diabetes and if you read everybody else's response, it's clearly ok to do the surgery. An in-person consultation will be needed to find the details of your condition and make the ultimate decision of the safetly of this surgery for you.
In my patient population, I'll proceed with surgery as long as their diabetes is well under control and they are a good candidate for the surgery. If your diabetes is not well controlled or you've just not really been checking it, then I would first go about obtaining a Hemoglobin A1C to confirm that your blood sugar levels have been reasonably controlled and I'd review your metabolic profile. These are simple labs that are done routinely prior to surgery for a patient like yourself.
You're already familiar with the possible complications, that doesn't mean that you're going to have them though. Everything lies within a range and your diabetic condition (diet controlled vs subcutaneous insulin pump) is no exception.
One last comment is that your surgeon can take some precautions himself as well. The surgery can be designed to be more conservative by limiting dissection and minimizing tension with internal sutures and less resection, using a binder that fits properly, etcetera.
All of these minor details will help the overall picture. It's not uncommon for body contouring cosmetic surgery patients to have some sort of health condition so I suggest proceeding with your investigation by going to a board certified plastic surgeon.