Let her know your worried about this
My Girlfriend Stopped Talking To Me, What Should I Do?
There could be a billion reasons why. Maybe you could ask her.
You need to go to her and ask her, why she is not talking to you.
Send her a letter asking her why she has stopped her contact with you and if there is anything you can do to make ammends. Take it from there...
Start talking to someone Else
Well, ask her if you did something wrong, if so apologize, also ask her if there is someone else and if there is that just means shes to much of a bitch to actually end it with you. Sorryz