Because as Amethyst thought more of why Emerald chose to just fall into slumber, this is the answer she came up with.
"She wasn't courageous enough to simply up and take her own life. And then the opportunity was suddenly presented in front of her."
She took a deep breath, "Ah I am injured, it is a head injury. Then I have an excuse. I can sleep, I can rest without anyone telling me it was too much. I am healing after all. So I'll sleep."
Diana hiccuped watching Amethyst interpret just what is happening in Emerald, somehow understanding why she was like this.
Amethyst looked back at them and smiled, "You can let her rest but you must never stop encouraging her. She can still go on, she can still choose her life. She can go ahead and rest but there are more fun things outside."
She walked over and passed Diana a handkerchief, "Then one day I can tell she will surely wake up. Because Emerald was able to hang on this long. She simply wanted to rest."