Calm down and think about whether your family is dissatisfied with other parts of your girlfriend, and then use this as an excuse to prevent you from being together. If it's only because of the zodiac, you can totally convince them with science. Or ask them to point out where they disagree. If they are superstitious, you can also tell them that old people often say that women will have more gold bricks in their junior year. The wisest way is to find the reason from your girlfriend and change it. If parents accept, nothing is a problem.