Try to look at life globally. Why do you live? What came into this world? What is the purpose of an unhappy love in all this? It's called to look for answers to existential questions" or questions of existence. Often feeling unhappy love is because we get hung up on it. And we must be able to look beyond the horizons of rigid relations.
Understand why you negative feelings. Sometimes from childhood we absorb the feeling that love must bring pain. So sometimes, if our parents lived unfortunately. Or if some sad story love has made us too strong impression. If you are chronically attract unrequited love, you especially should pay attention to this point. Try to think of other ways to achieve the purpose for which the moment of life need suffer.
Take a break from experiences. How much have the great examples in movies and literature, when star-crossed lovers went to the edge of the world to forget. And there are new feelings or new forces to live. And you try to escape from the endless thoughts about the pitiful fate. This will help you to find a new line of development.
Do not tighten the gap. If you are clear that the relationship was over, find a way to dot the "i". There is no need to pull with the gap where it is inevitable. The sooner you get away from the person with whom it is impossible to build a loving relationship, the better. The less you get emotional trauma, and the faster you will discover new possibilities of love. Now happy.