Why give insulin to a type 2, if the underlying problem is insulin resistant cells? Are there not problems with having too much insulin in the bloodstream?

Your question is a common one. The simple answer is that you need the exogenous insulin to overcome the insulin resistance that is present. However, a more sophisticated conversation about the causes of type 2 diabetes suggest that not only is insulin resistance present, but there is also evidence for simultaneous beta cell dysfunction. In those individuals that are insulin resistant, beta cell production of insulin increases. Those that make enough insulin overcome the resistance. Those that do not go on to develop diabetes. Roughly 50% of patients with type 2 diabetes end up on insulin therapy. Hyperinsulinemia has been looked at as a possible risk factor for atherosclerosis. However, it has also been looked at as an anti-inflammatory agent. The jury is still out.

JTL