There's no way to distinguish when that day will come, but it will. You will wake up one morning at peace and what once made you feel like you were stuck in an empty vast abyss disappears. It will no longer feel like you are stuck in an endless labyrinth with no sense of direction. You will notice the beauty that is everywhere that you never knew was there. It was there all along. The sun is brighter and the moon and stars more vivid than ever.
You will decide that this is the day you choose to celebrate, because it no longer serves you to stay in mourning. Somewhere between then and now, you've filled that empty void with rediscovered bits and pieces of yourself, or even pieces you never knew you had. The ache in your chest that used to bring you to your knees will be transformed into gratitude. You will be grateful for this rebirth because you no longer feel dead anymore.
Out of pain comes renewal and peace. There is so much to see in the world, so much beauty. You only have to open your eyes to it, even when your heartache has you on the ground and it hurts too badly. You can choose only to see the clouds covering the sky, or you can acknowledge that the sun is still shining behind the gray. Just because you cannot see it doesn't mean that it's not still there. It will be visible.