A Place for Vanishing by Ann Fraistat

A teen girl and her family return to her mother's childhood home, only to discover that the house's strange beauty may disguise a sinister past, in this contemporary gothic horror from the author of What We Harvest.
The house was supposed to be a fresh start. That's what Libby's mom said. And after Libby's recent bipolar III diagnosis and the tragedy that preceded it, Libby knows she and her family need to find a new normal.
But Libby's new home turns out to be anything but normal. Scores of bugs haunt its winding halls, towering stained-glass windows feature strange, insectile designs, and the garden teems with impossibly blue roses. And then there are the rumors. The locals, including the mysterious boy next door, tell stories about disappearances tied to the house, stretching back over a century to its first owners. Owners who supposedly hosted legendary masked séances on its grounds.
Libby's mom refuses to hear anything that could derail their family's perfect new beginning, but Libby knows better. The house is keeping secrets from her, and something tells her that the key to unlocking them lies in the eerie, bug-shaped masks hidden throughout the property.
We all wear masks—to hide our imperfections, to make us stronger and braver. But if Libby keeps hers on for too long, she might just lose herself—and everyone she loves.