Hi, I'd like to help you with your question.
It sounds like what you are experiencing is very normal. It takes a while to get over a relationship that you cared about. Give yourself time.
There are some things you can do to help yourself. Here are some suggestions:
Remove any reminders of your ex. Photos, letters or anything she gave you. Put it in a box and move it somewhere else that is difficult to get to, like an attic.
Spend lots of time with family and friends. Get out of your house on weekends and make plans to be with others. See a movie, eat out, participate in any activity that helps you stay active and away from home.
Go on a trip, either short or long. A change of scenery and new experiences helps you create good memories that do not have your ex in them. It gives you something to think about and smile about that does not remind you of her.
Remember that it is rare to not find another relationship. Most people who have been in a decent relationship already have an increased chance of finding someone again. But to insure that you do, get out there and start dating again. Make it known to people in your life that you are looking again. Go places where there are others you can meet. Join a group that interests you. It increases the chance you will find someone who has similar interests.
Here are some resources to help you:
Getting Past Your Breakup: How to Turn a Devastating Loss into the Best Thing That Ever Happened to You by Susan J. Elliott
How to Heal a Broken Heart in 30 Days: A Day-by-Day Guide to Saying Good-bye and Getting On With Your Life by Howard Bronson and Mike Riley
You can find these books on Amazon.com or your local library may have them as well.
Allow time to heal. Do not expect yourself to get over the relationship too soon. It took time to build the relationship, it takes time to get over it. Be good to yourself in the meanwhile.
I hope this has helped you,