I was in a slightly different boat as the triple negative cancer I had was very fast and had spread to my lymph nodes within a month between mammograms and then the cancer got into my skin and chest wall, but I had a similar regiment as you: 5 months of chemo and then 35 rounds of radiation (although with surgeries and a year-long chemo pill I also took).

For me chemo was the easiest thing I did. I had found a study online either through Harvard or the Mayo clinic where they had people fast during chemo - basically at 12 hours before and a few hours after. This really helped my side effects although I ended up fasting longer I had infusion on Wednesdays so I would have a dinner Monday night and then not eat anything until dinner Wednesday night. It kept my nausea down. It definitely recommend taking all the bowel movement medicines they give you, I skipped it for a bit and was in misery.

There's lots of great advice out here for managing the symptoms. I also lost weight but that was because I was 38 and had just had a baby so I was slowly shedding that as I went through chemo. The surgeries were harder on my body and the radiation, since it was every day, was too.

Good luck!