I wouldn't pressure her. You're probably making her more anxious about it by constantly mentioning it to her. If it comes up in conversation just tell her that if she ever wants to do it then you're the right guy to do it with. After that, wait until she's curious enough to want to try it. I understand about the whole wanting her to experience it. I love getting stoned but you've got to respect the fact that not everyone wants to toke, maybe that's because a lot of people aren't really educated on it but constantly telling them that it's really good and that they should try it isn't educating them, it's just pressuring them. Hope she come's round