Am i just wasting my time?

[john]

Me and this girl have been friends now for close to 3 years, initially she always text me but as time has gone on she's stopped, but we still talk almost everyday on facebook. I asked her once if she was just being polite with me and didn't want to talk but she said she wasn't and that she likes talking to me.
She keeps going on that she wants to meet my family, but every time i ask if she wants to hang out she's always busy; she is a workaholic, she is really focused on her studies and has a part time job as well.
We still flirt occasionally, but she says she just sees me as a friend, but i think that this is because she doesn't see me often enough. When we were at a party together she kept commenting that she was a good kisser and when we were on the floor together she didn't mind me having hold of her hand, and when i went to leave at the end of the night she gave me a hug which is rare for her. i joked the next day if i had tried to kiss her would she let me and her response was "who knows "

I just don't know what to do anymore, i like her and sometimes i get the feeling that she likes me too but i just don't know what to do anymore.
What do you think i should do?
How do you think i could progress things with her?
Do you think i stand a chance or am i just wasting my time?