I know what you’re thinking: I’m going to die alone with cats. But this is a myopic and selfish vision. Selfish because it presumes that we should use a relationship as an insurance policy: commit your life as protection against the possibility that you’ll become lonely or dependent in later life. One survey last month claimed 51 per cent of us are over-insured. And that, I doubt, doesn’t include people staying in mediocre relationships just in case.