Hello again, TopHat3435. You can beat her after completing the intro (where you're scripted to lose), at which point she no longer has 2 billion health and is completely yours for the taking
to make it more obvious we're scripted to lose, you should have her do some kind of full screen instakill attack after taking a certain amount of damage. so we don't just keep trying to attack her at the start, because I did that too for a while