I think, more than anything else, that the reason this world, this life, is hard to bear is because we're waiting for the physical of what is now only spiritual.
Sure, the perfection, and the ending of all hurt and sadness, and eternity of peace are all amazing, and I'd never belittle the wonder and excitement about that. But what makes the hurt of this world so very hard to bear? Why is it so hard to cast our cares upon Jesus now?
It's like a baby who's not content to just hear his mother's voice, but he must look at her, and take her in, and is unwilling to take his eyes off her - most beautiful to him. And he's not satisfied with just knowing she's there, but he has to feel her, and touch her, and hold her, be sure he'll never let her go.
So we yearn, and hope, and long to see you, Jesus. You in all your fullness, and your completeness. The symbols you've given us are not enough. I'm just a child, Jesus, and I'll always be one. I'll always be your child, and I long to touch you, to finally feel you, to finally feel myself in your arms, and to feel your hand in mine.
And on this earth, in this life, we will always be dissatisfied.
So we long for you, Jesus. We wait for you.