From what it sounds like, she wants to be interested in you, so you just need to given her a reason to be! I know its hard to do this with an attractive girl or a girl you like, but you cant act desperate. Play it cool, and try to demonstrate value to her and show that in fact she should be the one chasing you. Maybe go out to a party and talk to other attractive girls, talk to her mates, especially guy mates and gain their validation.
From past experiences similar to this, when i was chasing after the girl, she didnt want me because it was too easy for her, and she knew she could have me when she wanted, which didnt create value to the task of going for me. However when i made it difficult for her to get my attention, and made her work for it then she suddenly become obsessed with me. Try to switch about who holds the power with some negs and you'll be surprsied at the results. Despite if she is a bad texter or not, if you are on her mind then she'll want to text you
Zeus