Aw, I'm sorry to hear that, beast-n-beauty-queen. You need to be more careful who you consider to be your close friends. Grouping just anyone into that category only gets you in situations like this. Apparently, you trusted this person and they let you down. People do that sometimes. You can still be regular, non-close friends. At least you know how that person really feels about you.
Though, one thing I noticed from your OP is that you did a lot for her (introducing her to friends, studies...etc.), and for this you feel that she owes you something (everything?). Remember that in the end, she is an individual and you shouldn't expect her to just be your lackey forever just because of some stuff you did for her.
Oh, and cheer up :) In time it'll all seem like nothing.







