Ace considered what little Cora had told him about herself. She said Janelle was 'as messed up as she was' and he had seen that picture of both of them with matching Sharpie tattoos. There was a good chance that she self-harmed too.
He felt like he might puke when he remembered what else he had heard about Janelle. Her attribute was the injury one. Cora said she didn't know. And that her soulmate had killed her.
This was painting a very grim picture. If Janelle had spent years hurting herself and didn't realize she was also hurting her soulmate…had the soulmate lost it and committed suicide, taking her out with him?
Cora said her best friend bled out in her arms but didn't specify what happened beyond saying her soulmate killed her. If she thought that self-harming contributed to why the only person she loved died, it would make sense that she thought of it as disgusting.