Honestly, I would guess the chick is no older than 20 and I would advise you not to get all caught up in the whole situation and just continue to talk and chill with them. This girl is young and living and getting a feel for the world around her. Everyone does that in different ways promiscuity can just be curiosity. Friendzone could be fear. There is a vast amount of assumptions and mind reading you are going to attempt to do but you would only be taking the "potency" out of the experience. Sir, this woman more than likely will not be your wife let alone be in your life a year from now. Enjoy her for who she is and what the situation is and if you get "hurt" laugh at it and move forward( as if you have a choice) You will catch feelings here and there but keep proper perspective ALWAYS!