I appreciate your taking the time to tell your doings of this last year or so.
I share your fascination with the ability of our bodies to reverse damage from injury & disease, but that pales in comparison with the wonder at how much we have to return to smoking once the trauma has been subdued.
Vespera's recurring theme is that our connection to smoking is not merely a chemical link, but equally, if not more so, a psychological one. Your tale makes that abundently clear once again, and my personal experiences are in line with what you have just told us here.
There appear, from time-to-time, postings on the sites we all frequent, alluding to 'smoking genes' and their possible involvement in our inveterate dedication to enjoying and smoking tobacco. That might make up a tripod of possible supports for why we are so very fixed in our smoking pattern.
However, the 'gene-theory of smoking' would require some mechanism of action that ultimately requires DNA, RNA and enzymes who recognize & respond to the inhaled products from smoldering tobacco. That would make the process a chemical explanation, wouldn't it?