Welcome. You are not alone.
I was diagnosed with PCOS and Hypothyroid and finally early in my first pregnancy diabetes.
Make sure they check you for hypothyroid. It can affect trying to have a baby. Hypothyroid and diabetes (and PCOS) often coexist.
Do not be scared of insulin. It is wonderful to have the tool you need to control blood sugar well. I hate having diabetes, but I love insulin. It allows me to live my life (yes mostly low carb) and if I do splurge occasionally I can do something about it. I would recommend you talk to your endo about starting insulin even in the lead up to getting pregnant (you can use this time to learn how to use it and get comfortable with it).
I have always struggled with weight my whole life. I am only overweight.... but yes, people do look at you and think "if she lost weight, then she wouldn't have diabetes"..... but it is never that simple.... and it just aint true that it is your fault. But what is your responsibility is to work out how to manage it well (with this body that you were given)....
I used Dr. Richard Bernstein's "Diabetes Solution" as my bible. And it got me safely through 2 pregnancies with 2 healthy daughters (and through a few miscarriages ugh).... and still trying again now... if my old body will let it happen.
Ask lots of questions. YOu will learn heaps.