If you need to feel guilty, OK, understood -- but it's not going to get you too far. There are multiple factors that contribute to diabetes, and two people can have similar lifestyles and have different outcomes. So ... what do you do now? Moving forward? What do you want?
Assuming you want to be healthy as long as possible and turn this around, you have 4 parts of diabetic care to consider. Food, exercise, medication and testing.
No two people follow the same protocol, so every one who responds is only offering their opinion and their perspective.
You have to eat -- but what and how much? What were you eating that was making you sicker? What can you eat and get better? Certainly lowering carbs is helpful for many people. Not overeating is also very helpful. You can start by not drinking sugary drinks anymore, and switching to water most of the time. If you have a habit of stuffing yourself with pizza, pasta, bread, rice, corn, and sugary "goodies" -- well, those are considered less helpful options (even the alleged "healthy," brown, "whole" and "natural" grains, starches and sugars). Step away from the processed foods, especially the kind that come in crinkly bags or boxes that can sit on the shelf for years. Real food -- non-starchy vegetables, meats, poultry, fish, eggs. Cheese and nuts if you can tolerate them. If you must have fruit, eat an actual piece of fruit -- not juices void of fiber.
Exercise -- it's really helpful to get up and move, to challenge your muscles, to soak up the excess glucose. It also circulates your blood and immune system. There's all kinds of exercise -- from walking to the store or up stairs, to working out in a gym, to organized sports. It doesn't have to be complicated, but it does have to get your body burning off the glucose through use of muscles.
Being heavy, you will lose more weight from dietary changes and control than exercise, but they are both important.
Medication is sometimes necessary for Type 2 -- and usually begins with metformin. It's a drug that can block the release of glucose while also making your cells more accepting of insulin.
Testing -- it's highly argued by certain medical professionals and patients as to whether frequent testing is helpful for Type 2 diabetics. I think most people here would say testing is important -- but you can't learn much from occasional tests. Once a day means very little. You need to test before eating and 2 hours after eating, to learn what you glucose is doing, and how it reacts to different kinds of foods. It'd be helpful if you can begin a log of your activity -- sounds dreadful, but it's really helpful. Could be an app, or just a sheet of paper with columns for Date/Time, Food, Meds/Activity, Glucose. Look for patterns, and if your glucose goes up -- then you don't do whatever made it go up. If it went down, more of that.
While you're experimenting with all of that, you should also learn about what diabetes is. 1) Nothing to feel guilty about. 2) It's a medical condition. 3) There's significant things you can change to stabilize your situation, and to fix your future health. 4) Lots of opinions out there that sound very sure of themselves, but they are not you. You have to do what works for you -- and your new glucometer and quarterly HbA1C tests will be your guide. Learn what is a normal range of glucose readings (some say 75-95). You deserve to have normal glucose readings. And then analyze what is the underlying cause of your diabetic conidition. (Some believe that processed food full of excessive carbs and fructose cause the organs to become full of and surrounded by fat -- and that it's specifically fatty liver and fat in the pancreas that cause insulin resistance. And if you can burn the fat off via diet and exercise, and perhaps fasting, then the severity of your Type 2 resistance will "reverse" to the point of possibly not requiring meds, and having tests in the normal range.) All of this is a lot of work -- work that most people cannot wrap their heads around, and work that they are not willing to do. So, what about you? Are you willing to act in your own best interest, change course for your health and for your family, able to ignore junk food and traditions of unhealthy food celebrations, to get up and move like your life depends on it, and to use medication if necessary, and to learn more about your body than any doctor will ever be able to tell you?
When you get done feeling badly, and having a well deserved cry ... pick your head up and fight back. Discovery is Step #1. Proper diagnosis is Step #2. Now what? You don't want to get sicker -- you want to turn it around and get healthy, probably healthier than ever before. You are not your parents or grandparents -- genetics are only part of the equation. If you believe you "did it to yourself," then time to stop doing that. Time to be an adult and eat and take care of your health like a responsible grown up. Nobody is going to do it for you. People can be helpful and supportive, but all of the daily checking and commitment is up to you. Reach out and grab is hand and welcome aboard the path to a healthy new you. Glucometer, water, activity, avoiding high-carb foods, working with the health care system for feedback, and being way more appreciative of your body and health -- winner!