I'm about to leave the country to spend the summer travelling, however a few days before my flight I met a cool girl whom I kiss closed soon after.

My current impression is that there may be a possibility of something more than just sex there, however I'm wondering how to best proceed from here, as I won't see her for at least a few months. We've exchanged a few texts since then, so my questions are:

1) If I continue texting her while I'm traveling, how can I keep the spark alive so that I won't get put in the LJBF category when I come back?
2) She put an 'x' at the end of the first few texts but has stopped afterwards. How bad is that?