@kpkxrn , I'm so sorry that you are facing this. I remember the early days of my diagnosis, when the lymph nodes in my chest were pressing on everything, making it difficult to breath. I was down to a wheeze and coughing a lot. I had completely lost my appetite but as long as I kept eating even a little bit, I wasn't experiencing the nausea that you are describing. This sounds miserable.
Has your medical team offered any advice? Anti-nausea medication?
When are you scheduled to begin treatment? Hopefully soon, as you need some relief. Hugs.