Most Helpful Guy
Look, everyone has preferences. Some girls only want to date tall guys, or only athletes, or only black guys, or whatever.
The thing is, despite our preferences, we often find ourselves in relationships with people who don't match those physical preferences, because we've been won over by their personality instead. And for all but the most shallow of us, it's really a person's personality, not their body, that we choose to date.
So, clearly, dispite his preference for a different hair color, you've won him over with your personality. Ergo, you WIN! Just enjoy that and be happy.