First off you do not deserve to be alone and second you are right people suck and they change. I know it’s hard to find the words, but the only way things are going to be better is if you talk to your friend, usually it works best face to face. Try to get her to tell you why she has been acting the way she is and tell her how it is affecting you. Most of us struggle with being out going and it feels really painful to not have the support of a best friend. Keep trying to reach out to her but at the same time take care of yourself. Make sure that you are doing what is best for you even if it means not talking to her for a while. Most of all be kind to people, it’s really hard to make friends sometimes because it brings out our insecurities, but sometimes all you have to do is smile.