Why hasn't she replied?

I wont judge your uality, but it seems to me that she was leading you on, or maybe you where to be a one night stand. Either way maybe she doesn't remember you? It seems rather odd to me, maybe it's more of a professional and not a personal matter. Really it's hard to say, her actions showed she was interested in you, but her actions over the course of time didn't seem to follow, Maybe you got the wrong email or something? It wouldn't be the first time. But honestly just don't stress about it, your gonna meet someone and they wont do this to you. People come and go, and hey look at the bright sides because your bi you have a much higher chance of meeting someone because there is more people to pick from. Your feelings will p in time, or maybe she will get a hold of you. Maybe she replied to you but forgot to send it, try sending her one more message and if she doesn't reply then forget about it and continue on.