Lay the Heart Bare, Leaf by Leaf by IdleLeaves

Fracture

In an instant, the ice gives way beneath their feet.

I imagine this as taking place in an AU where Turgon has been lost on the ice and Aredhel & Elenwë found Gondolin together instead.

In an instant, the ice gives way beneath their feet. There's no warning, no deep splintering groan that often comes before the fractures; it simply cracks like a tree split by an axe, exposing the frigid water below.

Elenwë falls.

Aredhel lunges for her, very nearly sending herself straight into the sea, as well. Behind her, fellow travellers have come to her aid, holding her tight around the legs so she can stretch closer to the edge, reaching down to where Elenwë desperately treads water just out of reach. Aredhel extends her arm as far as she can; it's not enough. Elenwë's fingers touch hers then slip free.

Elenwë! Aredhel shouts, out of frustration, out of fear. She's already lost a brother to this death-ice; she cannot, will not--

Elenwë grasps her hand, and this time holds on. Aredhel pulls with all the strength she can muster, and those behind her do the same, dragging her back from the edge; then, Elenwë lies gasping on the ice, trailing water and shivering so hard her teeth chatter.

There are dry clothes for her, from Aredhel's pack, but they both know this will not be enough - Elenwë's hair is soaked through, dripping around her face and starting to freeze. There's precious little wood remaining to them and a fire is ill-advised on unstable ice, but without the warmth she will not survive. They've lost so many to the cold, already, though not as many as have been carried off by the sea or caught under the ice when it breaks and heaves.

The air is damp with heavy mist; the fire will not light. Aredhel takes the tinder-box herself and tries, over and over, until the smallest curls of flame start to sputter and smoke. Fingon brings them a heavy cloak - his own - and they huddle beneath it, grateful that the wind has quieted for a time. Aredhel presses a kiss to Elenwë's cold lips, and does not protest when Elenwë's head falls onto her shoulder and stays there for a long while as the fire grows and warms. Fingon sits across from them, wordless, adding wood to the fire as needed and keeping a close watch on the ice beneath them.

Aredhel reaches out, after a time, and takes Elenwë's hands, holding them tight in her own. They are chilled, still, but no longer frozen; white, still, but no longer ice-blue. I'll be all right, love, Elenwë says, and Aredhel believes her.