Do you think it is normal that I feel this way?
That depends. Why do you feel that it might be normal to feel that way?
Because I am the only person in the world who feels this way
It may be normal to you, but if it's not happening to others then it is not normal at all. You have to seek help so you no longer feel this kind of "normal" and experience the actual normal for the first time.
You are right. I wish my girlfriend was as obsessed with me as I am with the flavor.
I am sorry that you don't get to share things with your girlfriend because your tastes are not the same as hers or other people. You can always get that checked out so you can see why you don't feel like others feel. It might help.