You are a smart man and a very good man/person! Her skull is thick but I think you are making headway.
Next, when you have a positive situation where the feelings are good, standing just a little closer to her--change the body language a little: test the waters. Don't make too much of an obvious move. Just make SURE she's feeling the attraction. If/when she moves a little closer, don't 'go for it'. Watch and see what happens.
