Petey,
Slow down.
Even though it is not what you wanted to hear, now at least you know and the treatment can be adjusted. This is much better than to opt for a "mild" treatment that is not effective in the end.
So they will adjust the radiation field, good. It is also quite common to have chemo during the rad treatment. There are different options and agents, but it does not always have to be that debilitating. My guess is that if you are miserable you are more likely to post here than if you do really well. Therefore, what you read here may not be representative.

Remember you want to win the war and not just a battle.
In my case we changed the radiation field after we started rad tx. We also changed the chemo regimen twice. Above all, you cannot change the past and the decisions that were made then, try to accept them.

Clearly, this is no walk in the park, but you can do this! Just look at all the people here. It gets better if you have been in treatment for a while, I think.

I do like your pic, it is very funny. Humor helps.

Markus