People talk about "Aha!" moments. What about "I've stopped caring!" moments? Can you recall a particular instance, in writing or in life, where stopping caring was the cure? Where *letting go* jettisoned you forward, helped you get unstuck?
I've never stopped caring, but I've stopped worrying about the value of things. Like financial success, awards, the ratings on my books here on goodreads, or anywhere else. I think it's less about no longer caring and more about knowing what's valuable. The work is valuable. If you love what you do, you can easily let go caring if others do or do not. Although I admit it's lovely to hear that something I've made touches someone.