It's cold outside It's dark through my window And I can't tell If my eyes are closed So dark outside that the walls glow I'll just lay here alone They'll dance their lights in bliss 'til I fall asleep Fall asleep 'til the morning mist I am regret in the back of your head I am the song you try to forget It must be something deep in my blood I used to fall asleep to lightning bugs And now they left I haven't slept I haven't slept for months ♪ I'm fighting for sleep as you fight to stay awake My tired eyes are growing weak but There were lightning bugs before you left me Before you left me I am regret in the back of your head I am the song you try to forget It must be something deep in my blood I used to fall asleep to lightning bugs I used to fall asleep to lightning bugs And now they left I haven't slept I haven't slept for months ♪ I am regret in the back of your head I am the song you try to forget It must be something deep in my blood I used to fall asleep to lightning bugs I used to fall asleep to lightning bugs And now they left I haven't slept I haven't slept for months