I love turning to the book of Ecclesiastes when I feel this way. It helps me realize that, contrary to what the enemy would like me to believe, I'm not alone. Here a few verses that I'm really relating to right now:
All things are wearisome, more than one can say. The eye never has enough of seeing, nor the ear its fill of hearing. (1:8)
My heart took delight in all my labor, and this was the reward for all my toil. Yet when I surveyed all that my hands had done and what I had toiled to achieve, everything was meaningless, a chasing after the wind; nothing was gained under the sun (2:10b-11)
So I hated life, because the work that is done under the sun was grievous to me. All of it is meaningless, a chasing after the wind. (2:17)
All their days their work is grief and pain; even at night their minds do not rest. This too is meaningless. (2:23)
So here I am. Weary. Frustrated. Joyless. Tired. Yes, I'm even a bit grouchy. And I'm realizing that this is one of Satan's most powerful weapons: causing the people of God to chase after the wind. Making us hate life, because we touch nothing real or lasting. Making us feel like everything is meaningless. Causing us to go numb. Letting us dig ourselves into a pit of cynicism. Stealing our joy. And, in so doing, rendering us useless.
It IS a constant battle! It's a battle to cling to God's truth, to remember the wonders of who God is and all He has done for us. It's a battle against the lies that say we are sufficient in ourselves (or should be), and to surrender to the Holy Spirit. In times like this, I am so quick to forget how BLESSED I am! I am a child of God, and have received every spiritual blessing in Christ! I will not allow the world, the flesh, or the Devil to distract me from that. By the grace of God, I will walk in that truth. I can't change the way life is. I can't change the demands. I can, however, change my focus. I can stop relying on myself and rely on Christ in me, my hope of glory. I can realize I'm in a battle, take on the armor of the Lord, and FIGHT. I can deny my pride, fall on my knees, and receive the peace, and love, and grace, and mercy that I don't deserve. I can stop trying to figure out life (because my human mind could never understand anyway) and just live it! And not just live it, but live it to the fullest, enjoying it, because I know that God is good and powerful and in complete control. "Remember your Creator," Ecclesiastes says. Chasing after the wind is meaningless. Work is meaningless... unless you remember your Creator.