What do you think I should do?

There was this girl I liked and used to hang out with before... we'd hug and cuddle and stuff, but then I started to feel as though she was just blowing me off and totally ignoring me, so I started to do the same and removed her from my friends list on facebook because she wasn't talking anyways. Long story short, she got all pissy and emotional and appearantly it's all my fault, and I broke her trust. Anyways, I appologized and we started talking again... I thought it was all going alright... then she starts ignoring me again. Like, I'd understand if she gave me some kind of legitimate reason, and I have asked for one, but no she has actually admitted to ignoring me. I really don't know if I want to be wasting my time with somebody who doesn't even have the respect to acknowledge my existance... I'm pretty much at the edge here, and need opinions on the matter. I'm not a mean person... I'm relatively kind and understanding...I'd listen to her problems and try to support her... I'd always be there for her... I've biked 5k to her house at 3am just so she had a shoulder to cry on...It's not like i'm being annoying either... I'll message her once every few days to see how she is doing...What do you think I should do?