I need help in love (17)

There's a girl I like. I met her at school and really started to know her when we went out. She wasn't drunk but I was and still she wasn't drunk but she started to take my hands en she wanted me to hold her and stuff.

Then I started to flirt with her the next days for about 2-3 weeks.
She flirted back and showed me sings that she liked me (as example we texted each other for hours even at night). There was one week we almost didn't slept because we texted and talked that much. She flirted with me and I did the same thing with her.
As example she often flirted about her being nude or home alone and wanted me to come. Or she gave me some hints like she knew i liked her but still she sometimes talked about I needed to find a pretty girlfriend or if i liked someone. This she mostly asked when we where flirting. At that party there was another boy (a friend), she thought he was cute but she found him annoying. Often she said to me like: 'oh it's your friend again, he texted me. He texts me alot but i give you all attention' Or when we spoke in real life (we chilled and stuff) and she received a text from him, she showed me and said things like,' oh no him again' or 'man he texts me alot but i ignore him mostly'.

Then there was a school trip to Paris. 3 days long. In the bus we talked alot and she slept on my shoulder and took my hands. the first night she even slept in my bed (she sneaked up to my room). Then the second night it all happend... We (me, my crush, a friend and that boy that texted her alot) met up in a room. That boy flirted with her alot and she sometimes ignored it, but mostly she played him. I thought no worries, she is into you because she slept in your bed with you (she wanted me to hold her while we slept). Then later we played truth and dare. That boy asked me if I really liked someone and I said yes.... He said if she was in the room and I said yes again. Then the girl I liked shook! She was like oh no and stuff (i was stunned like what is happening) I stayed for another hour and left because it was awkward... The next day I found out she also slept in that other boy's bed that night... And she texted me she never wanted to show me extra interest or stuff like that... but that she really liked that boy, even before she met me. She knew that boy a few weeks longer then me... The next days we had some arguments but we managed to fix them.
Now at this point: She sees me as a friend because i kept my mouth shut and didn't asked her anything about that night or said about how I really feel right now (I did told her i like her very much). The boy doens't really flirt with her or talks with her that much. He says he doesn't want to hurt me, the girl says the same thing. Now I still text en she still flirts with me, but she often say something about that boy or when the boy comes i am nothing for her, it's like i disapear.... I don't know what to do... can I win her for me or does she even like's me more then a friend? At this point i feel being used for her selfasteam... but i really like her and can't really let her go...
Please i NEED ADVISE