Also: https://www.amazon.com/First-Book-Understanding-Diabetes/dp/B0044KMSNO
It's sorta geared toward younger T1's, but it's short, concise, and it was our go-to book in the first year. It's comprehensive enough and not some huge 300 page scientific babble.
The First Book for Understanding Diabetes https://www.amazon.com/dp/B0044KMSNO/ref=cm_sw_r_cp_api_glt_fabc_HXTJDJSA10EAJMX63EWB
Dude I love this book. It’s very concise and short. You can learn a lot about basic diabetes without getting overwhelmed. And then down the road get into the more comprehensive books. When we first were diagnosed I kept going back to the pink panther book.