Hi, I'd like to help you with your question.
It is understandable that you feel upset by the breakup. You mentioned you have tried to contact her several times. Since she will not respond to you, she may have a reason why.
One, she could just want to end the relationship and is done. In that case, you have a choice to either mourn the relationship and move on, or keep trying. However, if you keep trying it most likely will not change her mind.
Two you can continue to give her time. Call her or write her once more, tell her you will give her space and then let go. If she wants to come back, she will. If not, you will know.
If you feel you cannot let go after 6 months or more, please seek out counseling to help you deal with your feelings.
I hope this has helped,