Correct me if this is in the wrong category:

Background info:
Briefly met a girl 2 years ago and nothing happened (I was moving overseas/she had BF). I was home in the states in July, found out she was single, and we went out a few times, hooking up and staying the night each time. Ever since coming back to Europe we text, call about once a week (short <30 min), and always SPAM weekly (usually 2-3 hours, lately it's been in excess of 3 hours). We both love sex and it ALWAYS ends up a topic of discussion. I've been slowly getting her more comfortable with showing her body, having me touch myself, etc. (slow and steadily via SPAM).

Currently:
I'll be home for the holidays and am setting aside 4-6 days(the week she has off) to go and stay with her. As of right now our "relation" to each other is very ambiguous, never a topic of conversation and I think we are both avoiding defining it. However, she has acknowledged that she is single when she mentioned that her and a friend would be the only single people at a certain event. Since no ground rules, talks of exclusivity, etc. have been discussed I understand that we are both free to do as we please. She never mentions other guys and me girls. I make sure to see other girls to avoid oneitis and keep me sharp, but none of them can even come remotely close to her. Both of Our futures are up in the air as we do not know where work will take us during summer 2014.

I read "make her your GF" thread, but am having trouble applying it to a LDR. I'm not sure if I should continue to do what I'm doing and discuss it when I go to see her. Or should I address it if it comes up sooner. What would be some hints she might drop? She told me to look up a song the other day and the lyrics were very telling. THAT could always just be a coincidence, even though women are more meticulous.

I never bring up exclusive, I really feel its the girls job. If she wants to be committed she will let you know. When you see her just have fun and enjoy yourself.