We should have the right to have someone leave when we want, to only allow those in who we want in. But the truth is, people can force their way into your life whenever they choose. If they want to remind you forevermore that they exist, they will. They can reappear in a card or call or a "chance" meeting, they can remember your birthday or the day you met with some innocuous small note. No matter how little they matter in your new life, they can insist on being seen and recognized and remembered.
Deb Caletti (2012). “Stay”, p.150, Simon and Schuster