Hi there, sorry for the random question and long description.., but this situation is getting me crazy and cannot think straight..
I am normally quite good with girls, I am always in control and I play the game fairly well.. but this time I don't know what's happened.. when I see her I am lost.. I forget myself!

I met this girl 4 months ago through Couch Surfing (she is 28 and I am 30), she was new in town so we went for a drink and we just clicked! she is polish and had just moved to Argentina, we have been meeting frequently and going for drinks for the last 4 months now.. (from day one I felt that there was a strong connection between us but I did not know how to get to her..)
Two months ago I made the silly mistake of telling her that I was falling for her.. to what she looked surprised and told me that she was in love with a guy.. but it was an impossible story.. so for a few weeks we stopped seing each other, and then we went to the cinema one night and we were friends again. After that I thought that it was all lost, so I played it like the 'good friend' and stopped being so blind when next to her.. started playing a bit and even though she is very shy.. I got her to talk about sex, and to tell me lots of stories and I told her many sex stories of mine.. To my surprise she liked that a lot, and suddenly she was telling me all her secrets and fantasies and one night we went out and as the night was getting hotter and hotter.. we almost kissed.. she said that it was not the right night cos afterwards she was going to a party and a guy that she liked was going to be there.. I thought that it was an excuse so I took it as such.. no big deal, I could feel something in the air.. but I thought that it was just me imagining it..
Next thing I know, she is dating this guy from the party so I got a bit jealous and asked her to stop seeing each other for a while, as my hopes were out again and she was taken.. she did not like this but agreed to it. The week after I met a girl and started dating her, and we went to a party one night and the polish girl was there, she saw me with this other girl and she came to greet me, but it was obvious that her eyes were all over this girl that was with me that night.. after that, the week after she invited me out, one night to go for drinks.. we went out to this bar and got pretty drunk.. she asked me lots of questions about this girl that I was seeing.. and seemed pretty jealous about it.. she mentioned that this guy that she is seeing is not that interesting and does not seem to be that brave or funny.. and that he is not even her style.. that she likes more guys like me.. and then she went on to say that she likes guys with lots of balls, courage, that never give up, they keep on trying, she needs that kind of guy she said.. I went to the bar to get drinks and when I got back I saw that she had my phone and was going through my messages.. I felt that it was the moment so I asked her to sit down next to me.. she did.. and we kissed! It was great!! I opened my eyes to a big smile on her face and her eyes full of tears.. it had never happened to me.. never a girl cried just by kissing me..
The rest of the night was awesome, we stayed in the bar, we kissed for ever, she could not stop kissing me! She was going to the cinema with her best friend to a late showing, so I took her to the cinema, and that was the last time I saw her.. this was 10 days ago.. she is moving back to Poland in 1 week and I do not know what to do as the day after we kissed she said that it was a fantastic night.. she had enjoyed herself.. but she said that it was wrong cos we are both seeing other people.. She had invited me to a dinner at her house that same weekend but she then said that I should not come cos her boyfriend would be there and she could not handle to have us both there in the same room.. (they have been dating for 4 weeks now). Last monday we spoke on the phone and she said that from then on, she would ignore me.. that it was the best thing to do.. I asked her if every time that someone kisses her she cries and she said that she does not know what happened.. that she was drunk.. and I said that she was probably scared cos what happened was special.. and she said that I am seeing what I want to see.. and asked me to give her space for a few days/weeks.. the thing is that she is moving abroad in 1 week and I would very much like to see her.. I wrote a song about the whole situation.. she knows this cos I played it to her on the guitar the night that we kissed. Last week I went into a studio an recorded it with some friends.. and sent it to her on Friday, she did not answer that email..
Sorry for the long story.. my question is how do we know when to stop? She has obviously decided to bet everything on her boring boyfriend, I just fear that she could be also testing me to see if I go after her, try to get her anyway. I am so in love that I would follow her where ever! and I mean this..
points of view? ideas? next move?

Thanks so much for reading and for any words