NAH, with a dash of NTA. My husband is the same way and eats very specific foods, but the difference is that my husband is a really, really good cook. He learned how to make all of the stuff he likes (some of which I like too), but we mostly cook for ourselves unless we decide to eat something we both like.

You're not obligated to cook for your girlfriend, and she should definitely learn to cook for herself, especially if she's so picky. However, the reason I fall into NAH on this one is because it sounds like she has an honest-to-goodness disorder that needs to be addressed. We all have tastes or know people who are picky eaters, but she sounds like she has some serious aversions that aren't healthy since she has to take supplements to survive.