How do I get the elusive girl?

Ok, a few months ago i met this girl. when we first started talking and texting, it was fantastic, we were both into each other, we both told each other we were, we have a lot in common, and she is just so fantastic inside and out. im seriously falling on love with her. but then i asked her if she wanted to hang out, and she said yes, but she kinda blew me off that weekend we were supposed to hang out. i also asked her out to prom, and she said no because she didnt want to hurt her friend's feelings that already asked her out. but i learned from her friends who, who do like me (as a friend) that she just didnt want to go to prom and buy a dress, and that she told me that so she wouldnt hurt my feelings. one time she did ask me to go with her to a school event for english class with her in a group setting. i guess thats a good sign. well now we dont talk as much anymore, and sometimes she will be distinat and give me the "yeah lol" texts when we text, and other times she is really flirty and seems into me. i really really want this girl more than anything in the world right now. she is amazing and i love being with her. i should also probably add that in january, her boyfriend that she was with for 6 months broke up wither her the day before her birthday. how do i show her that i care about her and have her fall into my arms? i would never do anything to hurt her and i just want to be with her so bad. and the only time we can talk in person is in the hallways at school between classes because we dont have any classes together. and i cant call her because she has a large family and she gets no privacy. what should i do!?