Why do exes feel the need to contact you when you've finally moved on?

I'm not sure if its a coincidence or if the opps are following my every move.. And by opps I mean my ex because I am the happiest that I have been in a really long time, and here his a** is floating around in my message requests. I'll be honest, a part of me did want to respond to see what he had to say but I have grown so much and I no longer feel the need to hear it. This is Aaron 2.0 and I know that all this is going to cause is trouble and confusion.. and I no longer need that in my life. I have moved on with my life and as Nene Leakes would say, "THE DOOR IS CLOSED."

-This is what growth looks like!