After 3 months of icecream, rice cakes and cream cheese, I'm hearing you. Steroids don't make it easy either.
I'm far from petite and the 4 kgs I put on are stubbornly stuck to my arse. My thighs look like plastic shopping bags filled with scrambled eggs. It's insulting, and I sometimes think it is against the laws of physics--how can I have put on a kg overnight? It's not possible unless I got in the car, drove into town and gorged on Macca's. In my sleep!
Blame the steroids for the moon face and the back muffin. Worry about unpacking the rest when you finish chemo, you will be able to sort it out later if you are motivated to do it.