Maybe the secret to happiness is simplicity.

Why don’t you focus on where you’re going and less on where you came from?

There are laws. There are rules. And when you break them, there are consequences. Laws of nature and laws of life. Laws of love and laws of death.

Are you happy, Ivy?' he asks, surprising me.
In my whole life, I don't think anyone ever asked me that question.

Amy Pond: 'I thought... well, I started to think you were just a madman with a box.'
The Doctor: 'Amy Pond, there's something you better understand about me, 'cause it's important and one day your life may depend on it. [He Smiles] I am definitely a madman with a box.

He knows me better than anyone ever has. Than anyone ever will again. I would have stopped it if I could have. But I've learned the hard way, we can't choose who we love. Love chooses us. Love doesn't care about what's convenient or easy or planned. Love has its own agenda and all we can do is get out of its way.