I totally get what you're saying, and I also feel bad for her if the situation is as you surmise.

I went through the same phase. In fact, one particular favorite turn of phrase of mine appears on RinkWorks, namely the "Camelot's Curse" game in "The Early Years" anthology on Adventure Games Live. This anthology is a collection of AGL ports of some of the adventure games I wrote for the Apple II from 1985-1990.

The line in question, from a game I wrote in 1987 at the age of 13, is this: "The forest is so dense, the trees seem to move together, blocking your way."

The version of the game in "The Early Years" has this annotation: "The figure of speech about trees seeming to move together, blocking one's way, is one I latched onto and used in several places, everything from this game to a creative
writing assignment in 8th grade, which earned me an appreciative comment written in red ink by the teacher. But I have a confession: it was ripped off from a Choose Your Own Adventure novel that I borrowed from a friend. I barely read the thing, but that one line jumped out of a passage I read and impressed me, and it served me well for years afterward. Alas, that it is not mine."

Looking back on this now, of course, it's almost horrifying to me that I not only lifted the line, but I lifted it knowingly, and I reused it in three or four different pieces of writing -- at least the creative writing assignment and the game, potentially other short stories as well.

But, as you say, I think this was just a natural phase in my evolution as a writer and also, really, in growing up. I was 13, excited by the potential of the medium of prose, which I was just discovering, and experimenting with ways to make it vivid and compelling. The figure of speech, trees seeming to move together to block your way, created such a vivid sense of the claustrophobia and panic of being lost in a dense wood that I wanted to achieve that in my own writing, but I didn't know how to do it with my own words yet.

(The great irony is that, in retrospect, I didn't know how to do it with stolen words, either. The figure of speech is nice, but its impact depends on the context of a story and character the reader cares about, which I really didn't have.)

Now, I can write my own figures of speech. But would I know how to do that if I hadn't played with other people's in those earlier years? Probably not. In toying with writing I knew worked, using it and manipulating it and thinking about it and adapting it for other contexts, I'm sure I learned a lot about how prose works, what brings it alive, what makes an impression.

To this day, if I read a particularly vivid scene in a book, one that creates some strong imagery or emotional pull in my mind that I doubt I could have accomplished on my own, I'll go back and reread it and examine the mechanics of the writing. Sometimes it's interesting to see how little of a vivid image is actually explicit in the text -- sometimes something as slight as a paragraph break in an unexpected place can put a key dramatic pause into the reader's mental picture that clinches its impact. This exercise helps me in my own writing, but now instead of pulling whole passages, I learn by observing writing techniques that work, separating them from the actual content, and kind of absorbing them into the toolbox in my head.

I'm getting off on a tangent here, but my point is that even mature writers learn from other writers, even after progressing beyond the phase of lifting actual content. But a new writer, especially a young new writer, isn't just automatically going to have a natural understanding of form vs. content and how to fit the two together or pull them apart. A new writer is just going to see a piece of writing somewhere that works and want to experiment with replicating that effect, at first probably by lifting it entirely for the lack of any perceived alternative.

And there's really nothing wrong with that if you're truly trying to develop as a writer and not trying to claim credit for it. And even if a new writer does, the reason -- if naivety, as opposed to greed or pride -- can be pretty sympathetic and understandable.