> If so, what's the missing ingredient? I wonder...

I see what you mean, I think personally that ingredient is belief in a higher purpose, in the sense that my creative act is not just a capricious enjoyment on my part, or even a key component of my mental health, but that it can serve a function for other people and that that is the opposite of being selfish.

I'm still coming to terms with this idea.

I'm curious about your project if you don't mind sharing. I had a moment like that a few months ago and this book reached me after that. And FWIW my friend mentioned she re-reads the book and does the exercises every year, I can see myself doing that, and it's made it easier to not berate myself for not doing all of the exercises.