"Unless the LORD builds the house, its builders labor in vain."
-Psalm 127:1 (NIV)
Sometimes we just have to let go. When there comes a point where God is telling us to lay down all of our building plans and tools and just walk away. It definitely isn't an easy thing to do, especially if it's something you really desire or something you've put blood, sweat, and tears into.
I'm not advocating quitting because you're tired, or things get too tough, or because giving up is the easy way out. I'm talking about those situations when GOD is telling you it's time. When God has been speaking to your heart and you know in your gut (whether you want to admit it or not), that it's time to let go. Ecclesiastes 3 reminds us that seasons change... it may be a dream, a desire, a relationship, a specific plan.
As hard as it may be, the beauty of answering God's call to let go of something is knowing that He is with you every step of the way. He will help you and strengthen you. And ultimately, God is wanting to move you on to something better.