Marcel Zeelenberg, the world's expert on regret, joins Peter McGraw to discuss what makes a choice regrettable in the context of single living. They explore the nature of regret, its short- and long-term perspectives, and the concept of optionality for singles. They also discuss the anticipation of regret, societal defaults, and the importance of personal autonomy. Additionally, they touch on the value of regrets for learning and personal growth, as well as taking risks and stepping out of comfort zones in pursuit of happiness.