Why do people let themselves go after a relationship?

Anonymous
We broke up a month and a half ago. It amazes me at how round his face got and how his arm muscles that used to be buff are now not so very much in a short amout of time. He left me for someone else and he soon left her. I bumped into him the other day at work (I'm a waitress) and yeah he just let himself go.
Updates
+1 y
We used to be the workout couple. I got him into fitness. He started changing his diet as well with me.
Why do people let themselves go after a relationship?
6 Opinion