Paradigm Shifts and Maintaining Your Sanity

My life's is at an unreal juncture. Musically, I'm achieving all the little goals that I had in my head. And yet it does not heal me. I have a gig, a pretty major one, a week from now featuring the best musicians and the best music that has come out of Kolkata recently. I still don't know how I figured, how my songs figured in that list. It's somewhat nerve-wrecking having to sing songs by songwriters who I have admired and idolised all these years. I am super nervous. I am super excited. But the melancholy grips me like a blanket on a cold day. 

What am I doing wrong? Am I not working hard enough? Why am I in so much pain then?

All these opportunities that come my way, what good are they when my soul refuses to come out of the dark abyss that it's taken refuge in.