YA novel. Girl has no friends in high school. She meets a girl who leads her to a hidden room in the theater, where she befriends of group of students.

[Cheyanne]

I read this book around 2017/2018. It was about a girl who had no friends in high school. Until she meets a girl who leads her to this hidden room in the theater where she meets a group of friends that she starts to finally fit in. In the end it is revealed that the girl that lead her to the group died years before and she was a delusion that was never there and everything that the girl taught her was things that she overheard. I am pretty sure she was going to therapy during this but I am not sure. She does fall in love with one of the boys that she met in the room. She finds out that the girl was dead because she saw a photo and pointed her out saying that was her friend who showed her the room. I think that she had a break down because of this but I am not positive. Thank you.

[Kris]

Cheyanne, I removed the spoiler from the header, and added some plot details and a spoiler alert. (Spoilers are okay in the comments below the header - just give us a clear warning first.)

What's the genre (which we need to add to the topic header) - e.g., YA fantasy, mystery, horror, romance?

[Jessica (The Psychotic Nerd)]

Every Last Word?