Pain is essential to life.

When you lose someone you love , you feel your heart ache for a very long time. This is a true, real, physical pain. Your memories are then connected to your pain. Things you smell, songs you hear, sights you see, all trigger memories which then triggers your pain. You come to a realization though. They may have passed, but you're alive. You're alive and blessed with the option to keep on living.

Why do you think people say "pinch me" when they think they're dreaming? It brings you back to life. If we couldn't feel pain, we would have died off in the days of Eden. Young Cain says to young Abel, "Hey, go jump off that cliff. It'll be fun." Abel, knowing nothing of the fatality of the fall, would jump. There would've been no need for a murder later on in life, right?

So when the pain of heartache consumes you, you begin to feel everything. You're more alive than ever when you're in pain. It's the only time you know you're truly living. Pain is essential to life.