Alternate ending of allegiant

Chapter 49-TRIS

The death serum smells like smoke and spice, and my lungs reject it with the first breath I take. I cough and splutter, and I am swallowed by darkness.
I crumple to my knees. My body feels like someone has replaced my blood with molasses, and my bones with lead. And invisible thread tugs me toward sleep, but I want to be awake. It is important that I want to be awake. I imagine that wanting, that desire, burning in my chest like a flame.
The thread tugs harder, and I stoke the flame with names.Tobias. Caleb. Christina. Matthew. Cara. Zeke. Uriah.
But I can't bear up under the serum's weight. My body falls to the side, and my wounded arm presses to the cold ground. I am drifting...
It would be nice to float away, a voice in my head says.To see where I will go...
But the fire, the fire. The desire to live.
I am not done yet, I am not.
I feel like I am digging through my own mind. It is difficult to remember why I came here and why I care about unburdening myself from this beautiful weight. But then my scratching hands find it.The memory of my mother's face, and the strange angles of her limbs on the pavement, and the blood seeping from my father's body.
But they are dead, the voice says.You could join them.
They died for me, I answer.And now I have something to do, in return. I have to stop other people from losing everything, I have to save the city and the people my mother and father loved.
If I got to join my parents, I want to carry with me a good reason, not this -- this senseless collapsing at the threshold.
The fire, the fire. It rages within, a campfire and then an inferno, and my body is its fuel. I feel it racing through me, eating away at the weight.There is nothing that can kill me know; I am powerful and invincible and eternal.
I feel the serum clinging to my skin like oil, but the darkness recedes. I slap a heavy hand over the floor and push myself up.
Bent at the waist, I shove my shoulder into the double doors, and the squeak across the floor as their seal breaks. I breathe clean air and stand up straighter. I am there, I am there.
But I am not alone.
"Don't move," David says, raising his gun."Hello,Tris."