I'm sure we've heard the saying, "If you love someone set them free, if it was meant to be they will come back to you." Unfortunately, in most cases of separation it really wasn't meant to be. If a relationship has ended, chances are there were good reasons for it, either on our side or the other person's.
I kind of believe that in a sense we never really stop loving anyone. It may not be the same kind of love, but deep down there is still some sort of affinity towards the person. In many situations it may be this belief that causes people to hold on to a past love so strongly.
I'm too tired.