"
Hey, I was done playing games,
Knew I needed to upgrade,
So I went and walk away, way, way...
Now, you see I've been hanging out,
With another girl in town,
At least she doesn't bring me down, down, down
The guy was getting tired of their relationship because he feels likes they were just playing around not really in a serious relationship so he dumps the girl and started dating this new girl who he seems to like better because he get emotionally down with. Apparently the ex was seeing him date the new girl.