I'm not sure what this picture is trying to tell, but a picture speaks a thousand words, and I believe it speaks different words to everyone, just like a poem. I'll tell you what it speaks to me.
This woman is a nature lover who is sick of the world around her. Sick of urbanization, I presume, from the cut-down trees and lack of natural attributes in the vicinity. She's tired of trees being cut down and plants being perished, the world losing its greens and gaining grays. Her lack of fancy or flamboyant clothes also hints to her lack of urbanization.
She is alone because there is nobody to side with her in her fascination of nature, all her friends (if she had any to start with) and family members succumbed to the magic of urbanization. She may be dropping her book (a book about nature, it seems) because she's giving up on life, the falling of book foreshadowing her fate. The fact that she's standing near the water, and the water being a typical choice for suicide also hints to her suicidal thoughts. The apple swimming in the water might represent nature, swimming slowly away from the city and into a sea, only to sink deep down and get lost in there forever.
There really doesn't seem to be anything to improve here, though I can't help but notice that the apple doesn't sink in the water. There don't seem to be any trees around, so the picture can't be the moment of the apple making contact with the water. If it isn't a fallacy, I think I can see why: some parts of the nature always stay with the world. They don't sink. The firm tree in the background might also support this hypothesis.
Moving away from the story, everything about this picture is just excellent. The lines are decent, the colors are brightening, the shadowing is suitable, etc etc.
Keep up the good work, I really liked this. It deserves a nice place in my "favorite art" list.
10 out of 10, 5 out of 5. Good job.
~Review Request Club