I absolutely agree with everything caregiver states. Use of insulin is decided by a doctor based on many factors including how long someone has had type 2 diabetes and what regimens have been tried to get their A1C down. You don't say anything at all about what treatment you have received and whether you have made an effort to maintain a healthy weight, cut carbs and exercise. Type 2 diabetes is a condition in which the body produces enough or even excessive insulin but can't utilize it very well due to insulin resistance. Over time (many years in most cases) the body of a type 2 diabetic produces less and less insulin and that is when insulin injections are considered, not based on any particular A1C. Talk with your doctor or see an endo or diabetic educator.
This is an issue you should discuss with your physician.
Clearly, you have an issue with blood glucose control.
The medications and protocols vary with the individual treating physician.
As far as cardiac and kidney problems every medication involes a degree of risk and benefit.
Uncontrolled diabetes leads to a cascade of terrible events.
Insulin in itself does not cause cardiac or kidney problems.
You need to go to a facility that has diabetic care classes, attend them and ask questions. They are often staffed by an R.N. or a nurse practicioner and are very proficient at their jobs.