I can only imagine how hard it has been for you and how you hurt for her but please do not blame yourself about her having Diabetes. If that is why you feel guilty. I'm 99.8% certain that your Dear Daughter does not and will not ever blame you. Certainly, Diabetes can be a scary, turbulent path to walk especially in the early years of it. Some People have more difficult ongoing experiences. Sadly, some stay in Denial, Depression and/or other issues for many years which serves as a Big problem for them and their Loved Ones.
You say that your Daughter is so strong and does not let Diabetes get in her way. Excellent! Wonderful to hear. Although she may on occasion feel mad or resentful or have a down day(s) due to Diabetes or other connected circumstances, she will endure and her strength will bring her back up, I'm quite sure. I speak from experience since I was/am much like her. I have never blamed my Parents for my Diabetes because it is not their fault.
I'm sorry that you feel alone. I know that personal contact is the Best for most. My Mom went through the same feelings and worse with 3 little Diabetics. My Dad was off working and not surprisingly wanted -0 to do with Diabetes(although he had no choice sometimes). There was no one else in the area with Type 1 especially small Children with it. No one in our living Families at the time had Diabetes nor knew anything of it. But we all made it through those hard years and thankfully we each had a Future. Perhaps you could ask your Daughter's Endo if there are others in your Community and in your position or similar who you could get together with and share info and experiences and enjoy your time with.
Just Love your Daughter wholly, praise her, lightly advise her occasionally when needed and watch her bloom. Be Good to yourself. Congrats on her(and your)1st Successful year.