Thinking about someone or even something is a kind of longing. Maybe for the absent person, or maybe for the lost one. There are times when we just wait for 'again', and there are times when we know that the last 'again' is behind us. It would be easiest to forget, because without it, it's hard to build something new. And if something has already finished - accept that it is harder now and know that the sun will come out soon!