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interimdispose
Since: Jan, 2016

I found this request on another site (which was not English language), and it was never answered, but it caught my attention and now I'm looking for this as well.
This book was surely published before 2013-2014. It was most likely young adult novel; the author was compared to Hitchcock apparently? The story revolved around a teenage girl who was an only child. One day, when she was walking in the woods, she saw a wall (or maybe a mirror). Then she met a girl who looked just like her. Some time later, the girls switched places. One of them wanted to change clothes, and entered the other girl's house, because she was running away from something. In the end, it turned out that the main character had split personality (??) and the whole thing was just in her head.
Already checked the pages for Twin Switch, Tomato in the Mirror, and Split Personality - I don't think anything there was fitting.
Edited by interimdispose