I think it sounds as though you wanted her to have an emotional response to your email that from outward appearances it does not seem as though she had. It may or not be true that she did not have any feeling or response to your email. It is possible I think to have an emotional response to an email (although possibly not the one you wanted) and still go on to have fun. It may be that you took her more seriously than she took her words to you. She could be being glib because she was hurt by your email (not your problem or even necessarily your intent, but a possibility for her) or because she has had so many people she has run off, one more is usual or par for the course or even comfortable for her because it is so usual.
It seems to me the emphasis being on her, rather than your own good boundary setting and letting go of this woman thereby freeing yourself in a sense, is a bit off. You set the boundaries for you and I think that is a good thing. But her response is not within your control.