I feel like I’m somewhere in this comment. For me, the stress and worry about things going on in my life eventually led to full burnout. Those periods of flow were what kept me going, and when I could no longer find them, it only compounded the stress.
I ended up going on a self-funded sabbatical to focus on sorting out my personal and internal life, and the #1 change that has led to rediscovering deep focus was starting a mindfulness meditation and yoga habit each morning. These core habits led to changes in how I was relating to the worries and created space for me to sort through the underlying stressors.
YMMV, but I realized that some of the things I was worrying about were just consuming energy (despite being legit concerns), and I started actively reframing worries using some of the exercises in the book “Learned Optimism” (Martin Seligman, 2006). This book also made me realize how deeply hardwired my pessimistic defaults were, and these defaults were the source of a lot of my daily rumination and worry.
All of this to say, if you are at all similar to me, it might be worth considering the lack of ability to find flow a big red flag worth actively investigating. I don’t know if I could’ve avoided burnout, but I’m sufficiently convinced now that internal work is one of the most important (and accessible) ways of addressing this.