"In life, only one thing is certain, apart from death and taxes,

 no matter how hard you try, no matter how good your intentions, you are going to make mistakes.

You're going to hurt people. You're going to get hurt. And if you ever want to recover... There's really only one thing you can say. 

Callie: I forgive you.
George: What?
Callie: You made a mistake. But we took vows...till death do us part...so...I forgive you. 

Forgive and forget. That's what they say. It's good advice, but it's not very practical. When someone hurts us...we want to hurt them back. When someone wrongs us, we want to be right. Without forgiveness, old scores are never settled...old wounds never heal. 
And the most we can hope for is that one day we'll be lucky enough to forget. "

Episode 5, season 4 - Haunt your every day

"It's shocking how many kinds of addictions exist.

It would be too easy if it was just drugs and booze and ciggarettes.

I think the hardest part of kicking a habit is wanting to kick it. I mean, we get addicted for a reason, don't we?

Often, too often, things that start out as just a normal part of your life at some point cross the line to obssessive, compulsive, out of control.

It's the high we're chasing, the high that makes everything else fade away.

The thing about addiction is it never ends well.

Because eventually whatever it is that was getting us high, stops feeling good and starts to hurt.

Still, they say you don't kick the habit 'til you hit rock bottom. But how do you know when you're there?

Because no matter how badly a thing is hurting us, sometimes letting go hurts worse."

Episode 2, season 4 - Love/addiction