Is this girl just trying to be nice?

Alright, so this friend of mine seems to always be busy. Although thats what she says I have a feeling that she is lying. Heres the story: Me and this girl have gone on a couple friendly dates and they seemed to go well with lots of laughter and the occasional flirting ;) but now every time I ask her to do something she says she is busy. Sometimes she will even suggest a date to hang but later will cancel. Now if this was only for a couple weeks I wouldn't be asking you guys but this has been going on for more than 2 months now. I have tried to stop asking her to do stuff but thats when she asks to do something. I don't know its really confusing. I think she likes me more than a friend too because I have caught her staring(?) at me. I also like her but this busy thing is turning me off. Is she trying to be nice, playing hard to get, has no interest? What do you people think? Thanks.