River knows what people think about her. Fragile. Shattered. Damsel-in-distress. The truth is, though, it's just a bit difficult to remember how to be only one person at a time. In atmo, she can send a piece of her essence skimming down any one of a thousand silver cords. She can feel the muddy-earth acceptance of a pleased and placid cow remembering sky. She can dance with someone else's body, see tomorrow, go back and view yesterday. River senses everything. Even two poker chips mass-produced on the same machine have infinitesimally different ridges. Walls hum, but vents echo. Sometimes she can hear with her feet.
In the black, the cords dissipate, and it's a little easier to be merely River Tam, Simon's sister.
Before Miranda, her head was a mausoleum full of unavenged ghosts. They said things like what's going on and I'm frightened, like I starved to death in front of the refrigerator because I was too content to move, like he ate Mamma first and then he ate my sister. She dreamed their deaths. When she was awake they would shout at her and make her head spin until she tried to hide in the corner and cover her ears but it didn't work, it didn't work. Now they're quiet. She can think clearly.
Even in the black, though, she still contains multitudes. She is Inara, making a client feel valued; Mal, always thinking; Jayne, fascinatingly dull-uncomplicated. When she sits at the helm, Wash places warm, intangible hands over hers and explains the best route. And she's always light-streaming Serenity, underlaid with cherishing and wanderlust.
Crazy. Useless. Invalid. People who aren't part of Serenity's crew tend to underestimate her, but they couldn't be any less correct. At her best, River is stronger than strong and so very loved.