It's not weird. I hate raisins but love grapes as well. I guess it's just because you just dislike the taste of shriveled dried out grapes. Just because they are the same fruit doesn't mean they taste the same. My brothers love raisins but hate grapes. It's just the texture and taste they don't like.
Raisins have a much, much stronger flavor to them, and when the grapes are dried to create raisins, they antioxidants dry it, causing the flavor of the grapes to change tremendously. There is absolutely no problem with this dislike, so don't worry'