Everything is material. What else would you write about?
Someone once said (and if you know who it was please do tell) that a writer should not write that it started to rain, but should instead give the reader the sensation of getting wet.
Because of course, you tell stories not to relay facts (not even fictional facts) but to arouse sensation. Your reader picks up your book hoping to feel something. Don't disappoint her.
When it rains, let her feel her hair slick against the back of her neck, chilled to ice by every gust of January wind across the pond she just climbed out from.
Better yet, let her fear that no one will hear her call for help, no one will come to rescue.
Just never say that she is afraid.
You are a writer. You have ways to do this.
Into the Skin and Into the Water
You realize, of course that every character you have ever written, or ever will, is you. Even the one modeled after someone you know is you, because that someone you know is interpreted by your assumptions and biases, and those are formed by your experience.
This is an advantage. You understand abandonment, and mind-numbing grief, and anger, and fear.
Want to know what your character does with her fear? Close your eyes. Find the experiences that inform your writing of her, and climb through them beneath her skin. What do you feel?
Fall into the pond with her, and climb back out onto the sheet of ice that cracked beneath your feet. Call for help, and listen to the rustling of the cedar branches and the call of a crow strutting along the bank. Try to stop your teeth from chattering so you can call louder. What does your body do now? Does it arch its back to give the call a greater force? Does your voice squeak at the end because your throat has constricted? Does your chest shudder from some sick feeling beneath your ribs? Try calling once more. A little louder.
Do you hear anything?
Never Say Never Say Never.
The climb into your character to observe sensation and movement is a powerful tool to help you write about emotions, but it is not the only tool. Sometimes a well-placed reversal can leave your reader questioning why a character would do something he thought she would never do, and the answer he comes up with can be powerful.
Your character swore, all through the novel that (one) she hated Mr. Mandex next door who backed his truck over her dog two years ago, and (two) she would never enter the forest for any reason, not since she was lost there for three days when she was a child.
So on page 214, when your character stands on her front step still holding the note and the silk scarf he handed her just before he got into a car with his children to drive to the home of his daughter where he would live out the rest of his shortened life...
And on page 215, when a gust of January wind lifts the scarf from your character's hands and flicks it end over tassel across the fallow field into the forest... When she hesitates a long moment before charging across the field, pauses a moment more, and then follows the silk scarf into the forest...
You don't have to say much. The reader understands something important, whether she knows what the note says or not.