I don't have a book recommendation as I haven't finished it yet, but my pastor recommended Building a Non-anxious Life by Dr John Dell. It is in my kindle library to read sometime this year.
For me, my stress came to ahead back in 2019. I had returned from being deployed for over a year. Being state-side, I was still running at that same mental state to the devastation of my family. My wife one day finally said "we were better off when you were deployed." That lead to me getting a few counseling sessions.
Those counseling sessions attacked the biggest issue that was causing me stress, being addicted to my work. The biggest thing my therapist did to help me was tell me that I was replaceable at work and that work will never satisfy me. I was running the hedonic treadmill.
Since then, I have several things I do to keep my mind focused.
-I have scripture verses on my desk. One of them being See what kind of love the Father has given to us, that we should be called children of God; and so we are. (1 John 3:1) important to me that if even the things that stress me out "win," I am still a child of God, loved by the Father.
-Exercising regularly. When stress gets too high, I hit the road walking. But I also am doing cardio 4-5 times/week and strength training 2-3 times/week and that helps.
-Christian meditation. I'd like to do 10 minutes daily, but if I get it once or twice a week, that is a step in the right direction.
-I have a group of guys that I meet with on a regular basis. Usually weekly. We can share our stresses, reassure each other, and share wins.
-I still go to therapy monthly, though now to focus on other issues like PTSD