@magscratch: So sorry to hear you're still dealing with this but glad to hear your radition treatment is over. That's the good news. The fatigue will gradually improve, the variability is how long it may take. Most studies have demonstrated that fatigue from radiation is usually at its highest at the end of radiation, then starts to gradually taper with energy returning to baseline within a few weeks - although some tiredness can remain for a few months. Profound fatigue has been reported as feeling like exhaustion that doesn't improve after sleep or rest, so if that's what you're experiencing, it may help to know you're not alone. A lot of internal energy is taking place to repair cells that were affected by the radiation. Think of it like a race to the finish line for cell repair that your body is doing behind the scenes! You'll get to the finish line but the checkered flag will reveal itself so gradually you might not even notice.

Here is some information from Mayo: https://newsnetwork.mayoclinic.org/discussion/mayo-clinic-q-and-a-beyond-tired-with-cancer-related-fatigue/