Thats great. If she stays true to her words then you have nothing to fear! :) Just stutter on and joke abit about it, dont show that it is a disability for you, that might scare her. My experience is that how I handle my stuttering is what Its all about, if I get nervous about it and get low, then it affects the people around you. Go to that date with confidence. Im 31 years old, I have stuttered all my life. Stuttering is not a problem if you dont see it as a problem. <3