Congratulations on your diaversary! My 21st diaversary is exactly three months after yours, on October 8th.
I was going to post and say I hadn't fully "bought in" to diabetes, because I don't eat a low-carb diet and don't always exercise every day without fail (though I try to) and because I don't have the fantastic control many on this site have ... But then I stopped myself, because I do think I've "bought in" to diabetes. I look at the decisions I made yesterday and the decisions I make in comparison to my peer group (especially around food and exercise) and the fact that I'm very open about my diabetes (even if I don't flaunt it) and I definitely have "bought in" even though it doesn't necessarily reflect in my control.
I think for me being diagnosed as a kid it was a bit different. When I was diagnosed I wasn't the one who had to control my blood sugars, it was my parents. In fact, I don't remember being educated at all in the hospital regarding dosing insulin or anything like that. As a teenager I took over, but I did it sort of mindlessly. I used to eat things I shouldn't and then "not know" why I was high, and I went through a period of only testing about twice a day, but I never skipped shots or hid diabetes from anyone. Compared to a lot of teenagers, my "rebellion" was mild.
When I was around 23 I went through some sort of emotional shift with diabetes where I suddenly cared about it (maybe this is when I "bought in" fully) but also got really angry/sad/frustrated about having this when none of my friends had anything even remotely similar in terms of health to worry about. This was in 2005 and when I finally discovered the DOC, read every autobiography about people with diabetes I could get my hands on, and read books like Think Like a Pancreas to learn stuff I had never learned as a kid (I felt like I was re-learning everything from scratch, partly because in the almost 15 years I'd had diabetes things had gone from two shots per day to MDI). I asked my doctor to be switched to Lantus and MDI when it came to Canada in 2005, and then due to connecting with a friend in the DOC (and later in person) who used a pump, I decided to go on a pump in 2007. It helped my control a lot, but I am still working on that control bit ... Hoping someday I'll be able to stay between 70-200 every day consistently! Or else not care so much that I can't ... I think that part is an ongoing process, but I definitely think I've "bought in." I don't think I should have to contort my entire life around diabetes (like I was thinking originally) in order to say I've done that.