The insecurity you experience when an ex-boyfriend or long-term fling is with someone new feels kind of like taking acid. Everything you once felt about yourself has shifted. Your arms suddenly look different, your eyes, your hair, your nose, your jokes, your body, your voice, your day-to-day life, your family, your skin. Every detail you find out about this new girl changes everything you once knew about yourself. The things you liked about yourself you now question, and the things you thought you hated in other people you’re no longer sure you do. You acquire a newfound, non-chemical imbalance where you no longer know who you are or what is what.

When a guy I had been seeing on and off for years—one of those situations where you think the timing hasn’t been right because it’s a “long game” that will maybe end in marriage—got a new girlfriend, I began to tell myself the same tale I always do when I become obsessively insecure: “This person prefers every quality this girl has over the ones you have, or he would be with you and not her.” And why wouldn’t I think that? He is with her and not me!