Have you ever said or done something you later regretted? Or worse, have you not said or done something, and spent the rest of your life wondering how things might have been different "if only..."? Even if you're content with the choices you've made, it can be hard to let go of some of those missed opportunities. And if you're not entirely happy, those poor decisions and unresolved endings can really haunt you.
Now imagine the regret in question is a person you once loved. What do you do when that once-special someone suddenly walks back into your life? It could be that friend you crushed on in college, but never had the courage to approach. He's single now... and he's moving into your building. Perhaps it's your ex-- he's in recovery from the very issues that drove you away, and he's looking for a fresh start. Sure, you could ignore him, and let the history between you keep you apart. (After all, you had good reasons for breaking up with him in the first place, right?) Or....