Your general health going into this is an important factor in your recovery. That you do exercise in the form of those daily walks will work in your favor.

Please know that only a biopsy can determine if something is cancerous. The PET scan looks for areas of high probability. Sometimes there is something about the appearance of the nodule that suggests it might be cancer. There are hundreds of reasons a nodule might read a high SUV on a PET scan.

You mentioned that it solidified. Was it described last year as a ground glass nodule or opacity? That is often an indication that it is cancerous. That it has only grow 1mm in a year is good news. It means it is slow growing and not very aggressive. NSCLC tends to double in size every 7 months.

Surgery is usually only done with curative intent. Somethings you can do to help your recovery are to sleep in a recliner and walk a bit everyday. In cold weather it's ok to walk around inside your home. The hospital with affiliated practices I go to has covered hallways and connecting buildings. There's a one mile route that many use during inclement weather.