I make sure that this is more things and more enjoyable things in my life than just managing Diabetes! I also like (a non-religious version of) the Serenity Prayer as I spent a lot of time in my youth banging my head against brick walls (trying to change things I had no control over).
Maybe one of the most important things for me, which I learned when I got into recovery from my eating disorder, applies to diabetes as well. Whatever dietary changes you make still make sure that you find yummy things you feel good about eating. If food is all about what you can't have you will feel deprived and that won't work too well. When I contemplated whether I could remain a vegetarian with Diabetes (which I really wanted to do) I realized that I'd have to make major changes in my carb heavy diet of pasta and rice and cereal and get more creative in my cooking, which I very much enjoy.
Finally in diet, as well as everything else concerning diabetes management we all make choices; things we are willing to do and not willing to do. Kind of like in school, if you need to work twice as hard to get an A as a B, you can decide to accept the B as a good grade and spend your energy elsewhere. I read too many posts on here about "guilt" and "I shoulds" and "do you cheat?" My answer to the last one is always "on who??". My own example is remaining a vegetarian. If I gave that up I could eat Bernstein low carb and have better blood sugars. But I would be giving up something very important to me in that equation. Give yourself the permission to live the life you really want to live and see what place your D management takes alongside that. Then enjoy the hell out of that life.
Finally, find one or more "Diabetes buddy". Of course we all have 20,000 D buddies on here, but you all know the internet isn't real life! Find a group or just a friend. It's sooooo good to talk to someone else who really gets it.