Being "fat"

I'm 5'3 113 pounds. I warmed up two pieces of bread and a piece of cake I made. My SO kept telling me how disgusting it was I was even eating that because it's so fating and blah blah blah. And apparently I was being the annoying one out of the arugement. I'm actually pretty hurt by what he said and it's like I don't even want to eat all to prove a point to him.