I had the exact same experience. It just felt so... eerie, you know? As you said, like I was in her skin involuntarily.
It really is eerie. I guess it comes from the fact that we are basically observers that can't do anything to her. I don't know maybe the lack of a face to accociate the life that is laid before us is what causes this.
I heard lots of worse stories that happened to people that I at least know what they look like. The posts on r/alone are just text. You don't know for sure if the post is someone's real life or not. Uncertainty. Combine that with a depressing story and BOOM! Eerie feeling.
I'm just speculating though all of this might very well be bullshit.