/Cross posted on tumblr, for the picture I used as reference, go to my profile. Hope it gives you feels.
He stood against the door of the bathroom and slowly slid down it. He held his head in his hands. Limp pieces of black hair hung over his hands and hot tears ran down his chin. He could still hear their voices in his head. "Coward." "Cheater." "No-good-washed-up-nasty exbender." "You got what you deserved!" "Making us believe your lies! Why don't you us go back to that hole you crawled out of, monster!" He thought after a while, the insults would stop- that they'd lose their sting. Never. "You're the reason Amon's attacking us!" Sure, he did awful things, he cheated, took advantage of women and then left them alone, but he never wanted this to happen! He didn't cause this.
Swiftly, he stood and slammed his fist in the mirror in front of him. He barely registered the pain and flying glass as, he hunched over the counter. He looked forwards into his reflection. Grey eyes, partially hidden behind hair, stared back at him. He wasn't a monster. He wasn't!
He turned on the bathtub's water. He could try again. Maybe if his bending worked, they'd stop teasing him. Maybe they'd accept him. Maybe. He slipped into the water, felt his old element cover him. He lifted a hand and went through an old move, asking- begging - the water to move.
It stayed there. Mocking him.
He turned. His mirror laid in pieces all over the floor. One flick and it'd be over. One slash and the insults would disappear. He grabbed a small sharp shard and made one gash on his arm.
"For Amon…" He whispered
"For Shao and Ming.." Another.
"For the uh-vatar…" One on his chest as a small smile appeared when he said her name.
"For the monster inside me." Another on his wrist.
"For the cheating…" Another.
"For being me.." The last one on his neck, to the side. "…this is the last night, I'll be feeling like this.." he whispered.
Tendrils of blood swirled into the water and slowly it changed from clear water to deep red. He let the glass slip out of his hand and his head fell backwards. He felt one last tear go down his face. His eyes closed.
—-
"Hey! Anyone home?" Korra approached the last door in his apartment. Mako, Bolin, and Asami were waiting for her in the front room. She'd been trying to find him. So, here she was at the bathroom door. Her nose scrunched as she smelled something. Iron, she thought.
Korra pushed the door open to the bathroom. She moved forward looking down, shards of glass lay all around the counter. Korra's head snapped up.
"No…No. Tahno! Tahno!" Korra yelled as she moved to the bathtub. She pressed her hand to his neck, desperately trying to find a pulse. "Tahno! Please!….be alive!"
She couldn't find one. She pulled him out and covered him with a towel. Korra pulled his body to her, holding him fiercely.
That's how they found her, bloody and sobbing, hold the body of her best friend and boyfriend.