I know this is not a dating advice forum, but I simply trust you people more than people from other communities. 
Any thoughts are welcome and appreciated. 
I met a girl - 23 y.o. (8,69 on a 10 scale) recently, or she met me, to be more precise. Anyway, she approached me at a social event and was flirty as hell, (I even suspect that she might have silenced another girl I was also talking to at the same event) and added me in Facebook a few days later.
She has been quite chatty at times and has usually initiated the chatting sessions.
We live in different cities - some 200km apart so meeting up is not that easy. She has, however, shown interest in seeing me, most recently by being disappointed when I was in her city and did not tell her. So we agreed that we would meet the next time I am there.
We saw each other earlier on the Walpurgis Night when she made a point of waving and smiling to me (and only me) as I passed with my friends. We were in a marching formation, so I was not able to stop and talk to her. We had agreed earlier on to meet up in the evening and talk a little, which we did. She was rather busy organizing an event so she did not have that much free time. She was rather flirty, though. I spent the evening talking and getting introduced to other girls - most of them her friends, or at least aquaintances.
She started chatting again a few days back, and I asked whether she would like to go on a cruise and to an amusement park. She said yes, but showed initially less enthuciasm when I told her that I am going alone. She behaved teasingly when she realized I asked her out (like a small child would) and did not answer. I then told her I would go anyway whether or not she would join me.
She was a bit hesitant, saying that she is afraid of certain rides at the amusement park, and so on. I convinced her however, that it would be OK, and she basically agreed with me. I asked her again today to confirm the dates. She has an exam on the initial date I had chosen, so I offered to change it by a few days, as it does not matter a great deal to me.
It appears that she did not understand I was actually asking her on that cruise. She then said that she already had a boyfriend, yet then said she was not sure about her boyfriend, but that she needed to tell me that. She then said that she did not know why she told me that she had a boyfriend, and went on asking me whether or not it was a reasonable statement from her part. She then told me that she was not sure whether or not she would have a boyfriend in june, i.e by the time of the cruise. I would tell more about the female logic, but not here. 
Anyway, she agreed to the date, as I initially thought she was just joking, and meant that she did not have a boyfriend. And she agreed to coming on the cruise. Yet she then asked me why I chose just her, telling me that I have a lot of other girls I could have asked (she knows I have a-many female friends, quite a few are our mutual friends). I then told her that the only way it could be awkward would be if she had a boyfriend. She then confirmed it, by saying that she has one (had one yesterday) but was not sure if she will have one in june. Whatever that meant. Could have been a shit test. I then told her that her boyfriend would probably not like her coing on the cruise, and she agreed wit that - telling that she would not like it either if he would go somewhere with a girl.
She was still OK with the idea, but became curious as to why would I ask her. Is it an investement into a “friendship?” Then she wondered as to WHY would I ask out a girl with whom I had NO plans or ulterior motives.
She is about to get a degree in psychology, so I asked her to use it to figure out my motives, and told her that she impressed me more than other girls, as being the reason I chose her.
She then said that she would need to leave and we continue talking later.
I wrote, however, that she should not come if she does not want to break up from her boyfriend. On the other hand, that she should come, if she is not afraid of breaking up with him. She has seen the message, but not responded to it. She has responded quite quickly to most of my previous messages.
I am afraid I failed her little test. Or she genuinely has a boyfriend and is about to break up with him. Or she wanted to make herself more desirable, but it backfired. I am also afraid that my last message may have sounded as an ultimatum - i.e you can come only if you leave your boyfriend, I don’t want to see you otherwise.
Should I write back to her saying that she can come anyway, even as a “friend”, and try to flip the script that way? It seems she is hesitant in whatever relationship she has. With a bit of the right mones, it might get a happy ending afterall. Should I tell her I wrote that message because I would not like to get herself into trouble - even if nothing happens between us. I am also thinking of quoting/linking to an article about a man who was repeatedly raped by several women, so I could tell her that I feel safe that nothing like that would happen to me, because she has a boyfriend.
Or should I forget her by now [and ask another girl - 26 y.o. (7 or 7,5 on a 10 scale, yet with a very good personality and really into me, not playing any games)] and ask her in june whether or not she is single by then? (if it does not work out with the second girl, or whomever I will ask next) On the other hand it is a bit difficult, as several of the girls I am thinking about are friends with her.