The basketball does not care how tall you are or what gender you are. As long as the ball goes through the hoop more than your opponent, you win. It just so happens it is easier for the ball to go through the hoop if you are taller because there is less distance to travel and which results in greater accuracy. It just so happens that men are traditionally taller than women, so it only appears that men are better at basketball.
It all depends on skill. How good she is and how good you are. Spud Webb was only 5 '7 and he played in the NBA he is the shortest to ever play in the NBA and he won a dunk contest. Use him as inspiration. Look it up http://www.youtube.com/watch?v=y4zWLagc-14