How will I know when its love?

I am trying to move forward with my life, but a part of me (the main part) seems to be stuck on a woman I met last year.

I was in New Orleans, and I was high on life. I was doing things that most would dream of. And I was in the sleaziest street of the US. So, not only was I living in a bit of a dream state, I was a bit of an asshole as well.

Anyway I met a girl, whom I chased, but was really only trying to shag. But I was fighting myself at the same time. The real (good person) inside me, vs the horny asshole. It didnt work out, but I was having fun just chillin.

Along the way she introduced me to her sister (Amber), who was really nice. But I was not looking for anything long term, just some "fun". So I pretty much ignored Amber, even tho she and the real me (not who I was at the time) were a pretty good match.

And now, 6 months later, I cannot stop thinking about her. Not in a sexual way, but in a close, deep, caring way. I now realize how mature, intelligent, unselfish, caring, open, honest, and confident she was. And I am halfway around the world, back in AU.

Thinking of going back there, but the chances of her working in the same place, 6 months later, are pretty slim. So I guess I need to move on. But was it love, or just something else? I need to know, so I do not make this mistake again.