First, I would say that a Christian, no matter how dark the season of his sadness, never is completely without joy in God. I mean that there remains in his heart the seed of joy in the form, perhaps, of only a remembered taste of goodness and an unwillingness to let the goodness go. This is not the “joy that is inexpressible and filled with glory” (1 Pet. 1:8). It’s not the joy that we have known at times and fight to regain. But it is a fragment of such joy—like a man who sits in prison and pulls out a tattered picture of his wife...*
But the joy is there. Cling onto it, remember it, savor it, strive after it. It is there. We have joy in Christ today and in that He has called us. Don't let go. Bury yourself in the Word and prayer and rely on your fellow sojourners to see you through. God will enable you through your difficulty.
*Piper, John (2006-12-14). When the Darkness Will not Lift: Doing What We Can While We Wait for God - and Joy (Kindle Locations 437-440). Good News Publishers/Crossway Books. Kindle Edition.