This happens to me a lot. You mentioned before that you are normally not a peaky eater. I am, and it sucks cause almost everything makes me want to vomit. I don't like any kind of cheese, pizza, most vegetables and almost every sauce. Even the smell of those things makes me sick. I would like to like those things, but i really can't stand them. So my diet is basically simple pieces of meat and rice. I've recently noticed that I can't eat meat either without retching because it just feels so gross. Sometimes I may like the flavour of something but refuse to eat it just because it seems so fucking gross.
I really hate the concept of hunger. Having to be constantly feeding our mouths to avoid pain and dying, just to be able to eat more, while causing lots of pain and death to others in the process...
