first of all I just wanna say never question your beauty as a black woman. like all men, there are some who are going to be sexually attracted to you and some who won't be. if you are a beautiful woman you gonna be beautiful no matter what society says about black women.
my thing is, why do you prefer white guys? lets be real, most of them DO NOT like you, or black women in general. whenever I meet someone who strongly prefers a race that they don't even belong to, to the point where they refuse to date within their race, they almost always have serious issues about their race. its not mentally healthy to put white people up on a pedestal like that. especially not when most white guys are not going to take you seriously. black people with fetishes usually find themselves heartbroken when they realize the person they're dealing with either can't relate to them deep down, or subconsciously sees themselves as superior.
look at the world around you, look at the media, notice how many Americans (whites included) believe what they are shown in the media. search "black girls" on this site and find a lot of negative things that are written about us.
i hate to break it to you but most non-black guys do not have anything good for black women besides maybe some sex. I do not date white guys but I have been hit on and asked out by them so I know that some are attracted to the features of black women. it's just that you will have a exponentially higher possibility of getting used and not taken seriously by a white guy and his family, friends, etc. and to me I don't think its worth it. Sorry!