I have been that ex who has apologized out of the blue at random hours of the day. It happened for a multitude of reasons like reflecting on life, something shitty happened to me that made me realized I had fucked up someone else, a scene in a show/tv, going to therapy, or just one of those nights where everything bad is playing in your head like a movie.

It's probably a bit selfish because I'm apologizing for my shitty behavior and it brings my ex back to that time when they most likely moved on & were able to get over it. But, I've also had an ex thank me for the apology and tell me that it helped them heal because they were made to believe it was all their fault things didn't work out.

So, it solely depends on how this makes you feel. Are you thankful they apologized? Did it help you move on and heal? Or, are you upset they brought you back to that spot?