Knowing when it's the End

How do you know when a relationship is truly over? Can you just sense it? What if you think everything is going good only to find out that you were misled? You ever notice how people that barely know what's going on always say things like, "You guys looked so happy. Are you sure you can't work it out?" But what do you say when people that are around you a lot of time say things like, "It makes sense. I saw it coming a while ago." If they saw it coming why didn't they say anything to you? Would you have listen if they had? Most likely not. We all too often tend to miss all the little hints we are given. Maybe it just becomes habit to be with the other person and live the way you have been living. Who knows why we miss or overlook these things. Some of us are just in a world of our own.