Do NOT beat yourself up about this, it takes the perfect mix of diet, exercise, carb/protein, and yes even medications to get this under control.
The important thing to remember is you do NOT have to be on insulin the rest of your life, you can get off of it when you get things under control.
I help people with this all the time.
Get on line and get the My Fitness Pal application, load it on your computer, phone, and tablet (if you have one). Document every single morsel of food you eat. You want to set you calorie range for aprox 1-2 pounds of week for weight loss. NOW here's where it gets tricky. YOU absolutely, HAVE to eat a well balanced HIGH protein LOW carb diet.
Carbs are what break down to sugar, what can't your body break down? Sugar - YUP. That's why you now have insulin, because your body has become resistant to making it. SUCK. But if you are not fueling your body with the wrong stuff, your resistance will diminish.
1. Remove any and all things from your diet that contain the evil and dreaded "HIGH FRUCTOSE CORN SYRUP" This stuff is the nectar of Satan, and will just fuel your insulin resistance.
2. CUT OUT ALL PROCESSED FOODS; Yup all of them, processed lunch meats, ick get rid of them, and of course things that are carb based that are white. Bread, Pasta, Rice, if it's white it's processed or a simple carb, and becomes sugar....which you cannot break down.
3. Fuel your body within 30 minutes of rising in the am. Give yourself good protein primarily. Quick easy choices include smoothies made from Greek Yogurt, and fresh berries, yum. You can also get good quality protein shake mixes from just about any vitamin/supplement store.
4. Fuel your body every 3-4 hours throughout the day, not a ton, but making sure you are giving it good proteins, and satisfying foods. Like a TBSP of Peanut Butter (low fat, check the label, make sure it doesn't have the dreaded high fructose corn syrup). and half an apple. String cheese, and celery. Handful of nuts, and some grapes.
You want to keep your metabolism up and running throughout the day, not starving yourself. If you are feeling hungry, then you are not getting enough of a good balance.
This may go against anything diabetic educators, and dieticians tell you, but trust me this works.
I know it's frustrating but really your Dr is doing you a favor by putting you on the insulin. It is going to quickly get blood sugars back where they need to be, and prevent from doing any more damage to blood vessels, kidneys, and extremities.