I've often wondered if depression and anxiety serve a positive purpose. A very simple example of this: if I've lain awake at night worrying about all that I have to do, the next day I generally feel compelled to get stuff done.
But this is the first I've considered that depression might be an immune response, and I find that fascinating. In that way, one could argue that all symptoms of any kind are immuno responses. Instead of trying to find an anodyne for the symptoms, which is the basis of western med, perhaps we would do better to view all symptoms as messages from the body, and good messages at that. They are saying "I, your immune system, is on the job. Fear not."
Very interesting post. Thank you for putting it together. I am glad you persevered. How is your dopamine level now? Are you ready to write the next one?