This is incredibly beautiful. I love how it flows so smoothly together, despite your using separate resources for this manipulation.
If I was never told that this was a manipulation, I would have immediately deducted that this was a painting you did.

The reason why I was so immediately drawn to this piece was because I have an original character named Lyla who plays a major part in a story I write on the side. That's the sort of dress she'd wear all the time (without much variation, there aren't exactly options for her) and she has long dark hair flowing down her back, against her porcelain pale skin. She also happens to play the violin. Quickly, I'll say that she lives in a post-apocalyptic world and your background as well as the way the figure is situated upon the rock looking out toward the world, reminds me so very much of my character.
Which is why, along with this entire piece having an alright enough visual 'hook' to pull me in, this piece was able to impact me enough to type out such a long crit in the first place. I'd love to give you a little bit more in terms of stars but I think in all art, there is always room for improvement. I'll wait until you knock me over my chair with your artwork for me to give five stars. XD

As much as I am drawn visually to this however, the one problem I have is how abruptly the sides were cut off on the top right above the model's head and on the side to the left of her. Why? Because in my mind as I envision a better composition (my opinion of course, you don't have to take it), if the model's head was turned toward the right to look toward that direction and the side was extended on the -right- side to make it feel as if the model was looking out toward a dark panorama of the world folding out before her, it'd be quite effective.
I also have a bit of a bias against square compositions since generally they don't work out as well as rectangular compositions do.
If you do keep her face facing this way however, I'd wish that we could see more of what's in her peripheral view or at least have the side extended out a bit (and cut back a little on the right side). I feel that at the moment, I am looking at a piece of a painting, not the entire thing.

What I'm saying is that there's so much potential to be unearthed for this piece-don't despair. I think it's brilliant. But brilliance is never flawless, of course.

The flow of your piece is very poetic. When I look at your piece, I really feel that I am reading a visual poem. There's butterflies disbanding in silent flourishes from the violin after it has played its last song, sweeping away against the folds of her dress-as if music will always live in the air even when the girl doesn't want to feel her music anymore. There is black upon black in the dark of the evening, along the dress folds bleeding into the shadows of the cliff and the light in the sky beginning to fade. There is cold rain gracing all that it touches, with a cold, melancholic touch. The world is bleak, there's a feeling of wanting only to resign, to accept the inevitable. And all hope is leaving fast in the form of these metaphoric last signs of life, those butterflies, quick into the air to find the last of the light before it turns into the darkness that would cloak the world in night as well.

I really love your piece and I think a lot of improvements can be made but as far as things go, this is an excellent start.