Unless you're fortunate enough to have an ex that lives on the other side of the country, or better yet, the world—it's inevitable that you one day might run into them.
Of course, there are many schools of thought on how this scenario should be handled and I will do my best to cover all of them. This is a very individualized circumstance, based mostly on how you two ended things. If that POS cheated on you, you're obviously going to have a much different reaction then if things ended amicably (LOL, is that even possible??)
Personally, I don't enjoy physical exertion all that much so running isn't necessarily my go-to, but it's super effective nonetheless. Obviously you aren't going to break out into a full on sprint, but just start VERY briskly walking away. The further you get, the better. If the space is crowded leaving you no room to dash, don't fret, there's more options to come!
Now THIS one is my favorite. I do this ALL the time in my hometown. I've successfully avoided people I've known for years by simply making myself invisible. No joke, I was standing behind someone I went to high school with for 20 minutes at a train station the other day and they had NO clue. Head down, sunglasses on, hat if you have one with you and BAM! You're practically a Kardashian avoiding the paparazzi.
The casual wave is sort of a cop out, but that's exactly the type of person it's designed for. This maneuver is meant for a person who can't commit to a single feeling. You want to be a dick, but you also feel bad, but you also hate this person—you're conflicted. If you're going to casually wave and NOT commit to a conversation then you must run shortly thereafter, it's key.
The first time I saw my ex of 8-years, he was jogging at the track about 100 ft from my house. He had the option of running at probably 68975867898765456789 different locations, but he decided to do it where I can see him—FROM MY DRIVEWAY. I did cry, mostly out of frustration at his obvious manipulative BS, but I wasn't ashamed. It actually felt kind of good to let it out. I haven't cried about it since—which a therapist may suggest is the suppression of my emotions, so good thing I don't have a therapist, amirite??
Similarly to the casual wave, this move means you can't commit. If you're going to flip someone off you should, in theory, be able to tell them to f-ck themselves—with words, but you're not like that. You wish you could be the angry, "you don't mess with me and get away with it" sort of person, but to no avail. Is this cowardly, sure? But think of it as road rage, minus the car, plus the beotch who broke your heart.
Even if they did break your heart, once upon a time you loved this person. While this option is the most difficult, it's the most respectable and if you're able to pull it off, my hat goes off to you—sincerely.
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