Acidity is the killer with anything creamy. Think about any time you have added a squeeze of lemon juice to a glass of milk, would you want to drink that!? No I didn't think so. With that in mind think about what will happen to that lovingly prepared creamy spaghetti carbonara when you add a really crisp acid Marlborough Sauvignon. At some point the wine will curdle the sauce and that, in a nutshell is what makes it just not work. Unoaked Chardonnay is the classic match.