There's not much you can do to change the decisions they've made, but you can reflect on your decisions and see if you want to try to change anything about yourself.
I don't know what exactly you're referring to when you say "misbehavior," but sometimes the stank will never come off a relationship after that. Also, people grow and over time may naturally drift together or apart. Could be you're still "misbehaving" but aren't aware of it.
No. Stop. Don't.