Susan,
I totally know your pain!
I had pain after treatment when I ate bananas, chocolate and alcohol (like wine). My mouth felt like it was on fire with pain when I ate any of those things. It was the weirdest thing and no one could explain why. Everyone's reaction to radiation is just different.
Good news though, I can eat chocolate and bananas now without pain. So it did get better. Alcohol still stings. I am about 10 months out after treatment and it was around 7 months out that I was able to have chocolate again.
Laura