Thanks for the suggestions, here and on social media! It was tough to choose, but I’ve decided to go with Dannydangerously’s suggestion. “Shot in the Heart” by Simonne Darkstar came a close second.

Heartless 

Pain shatters my heart like a grenade.  
“Don’t be ridiculous,” I say to the splintered organ.  
The fragments pulse and bleed, and I, shell-shocked,  
take out my chewing gum, glueing together what burst apart.  
“Don’t be ridiculous,” I say again, sticking the oozing mess back in my chest.  

On the train it falls out again, through the gaps between my ribs.  
I pretend it didn’t happen, ignore the curious glances,  
ignore the melodramatic organ lying splayed on the dirty floor.  
Pretending to tie my laces I pick it up and slip it into my pocket.  
“Don’t be ridiculous,” I hiss.  

In the afternoon, between emails and phone calls, I feel it playing up again.  
“Don’t be ridiculous," I say once more,  
now angry, for I have deadlines,  
and the mess on the floor  
And the absence of something pumping my blood  
Fuck up my schedule.  

“You are ridiculous.” I say.  
“I’m better off without you.”  
And I sweep it under the rug;  
quickly, as there’s a knock at the door.  
To dispose of later.  

And at night, as I lie not sleeping,  
My blood frozen in my veins,  
I feel a dull phantom pain explode in my chest.