A few lines from LeeRoy Brightmane's Personal Logs:

Immortality is the greatest blessing and an even greater curse. Though, oddly enough, not the greatest curse. The greatest curse is the curse of sleeplessness. Which is a curse that I too have. 

Yeah, you'll never die. That's great, you can accomplish anything you have ever wanted to accomplish. As long as you have eternal youth, you're golden. The problem is, you get bored. After you've sailed all the oceans and seas, climbed every mountain, built your dream home, found love, married, lost love, remarried, lived out your loved one's lifetime, had children, raised children, adventured the world, killed a man, and everything else that mortals do. You get intensely bored. 

A crippling sense of ennui washes over you, and you begin to lose motivation to do anything. 

Humans weren't meant to be immortal, the wall that I can never pass, known as death is there for a reason. I accept that now. Mortals can live true lives, lives full of meaning and passion. Every one of their actions has meaning, because they put their heart and their soul into it. Time is limited, so time is precious. 

But for me?

Well. Time means nothing to me, except how long it will take me to do something.