in my experience, some people have to have another half, always. They line up the next one, to try and make sure there are right, before dumping the current one. One of my best freinds did this with the 4 men she married/ lived with. Every single time she met the other one, decided if he was better than the current model, and then dumped the old one. Some people aren't so dependent on having to have another half. My brother is the former- when he told me he was moving out to " have some time to himself" I said" so who is she?" he was pretty shocked ( It was the next door neighbour). Just depends.