We often feel that if we love someone, we must think of him or her. In fact, if someone tells us that we stay put in his memories, then we feel assured that the fellow loves us. Isn’t that which is taken often as a mark of love? “Oh! I think of you so much. Oh! You have occupied my memories and mental space.”
That is not love. That is separation. Only that which is away from you needs to be arrested in memory.
Real lovers have no need of remembering each other. They just are with each other without distinction, one without a boundary. And that obviously cannot happen with two bodies. Between two bodies there would always exist a boundary.