There is not much of a way around people getting freaked out. It is going to happen. I always thought that it would be better that they do that before we meet or even talk to one another because then there would be no chance I would invest even the smallest amount into them being an option. For that reason I told everyone up front and posted it on my dating profile. I didn't even want to know anyone that would freak out. Why would I want to experience that.
Now that you have set up a date, I would get right on it and tell her. I like what Mono said about "meaningful".... then don't fuck her.... for a long time.... like after three dates of something. That will indicate that you seriously want to know her and connect with her before having sex... open is usually seen as having sex outside of marriage and that ones partner knows about it. Or it can mean the person is openly cheating on their partner. No sex-not open. That's how I see it anyway and I would assume that those you date would also.
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