Should I continue to be friends with these people?

[rms_98]

I know it's quite immature, but I am wondering if I should be friends with these people. I've been very close to one friend, whom I shall call Anne. But ever since the holidays have started, she's been meaner and meaner to me. I try to ask her why, sometimes, but she doesn't tell me why at all. Then when I try to strike a conversation through texting, she keeps saying she is at tuition. It became more and more awkward until it came down to the point of us unable to be in the same room. Then now all her other friends have been acting very mean towards me. For example, when we are on twitter, I post something, and they will get very personal about it. And their tweets are mostly directed at me. I've given Anne so much things, materialistically... and I don't get any niceness back. It's really heartbreaking and I don't know where this friendship is going... I'm really upset and I've tried talking to Anne about this but she is just plain mean to me. I just don't know what I should do right now. I really need some help!