Fuck, just typed up a long post about all sorts of shit, even referencing Dale Carnegie’s How to Win Friends and Influence People but it all boils down to this:
Be honest. No matter how much it hurts you or her.
It won’t be pleasant. She won’t understand. You won’t feel good about it. It will hurt. There is no easy way. For the good of both of you, just muster up all your confidence and tell it like it is. Do not leave any false hopes.
Fuck all the bullshit. Tell it straight and git er done.