There is stalking, a character is sent messages from her own phone showing pictures of herself in her home, the stalker also shows up outside of her house multiple times throughout the film
Though the movie doesn't reveal this until the end of the scene, it only happens in the protagonist's imagination: she runs from the back door, he catches up, and he graphically, gorily smashes her head in. Her head is off camera during this, but gore flies into view. Her bloody head is seen after he stops.
Relatively late in the movie, the protagonist's right hand gets brutally smashed; it's never covered up, so from this point on, it's often on screen, her bloody fingers broken and bent at different angles. It's a disgusting (if not all too real-looking) prosthetic.
the main character is deaf so her phone flashes when she gets a call and her fire alarm is a bright strobe light that goes on for a couple minutes two separate times in the movie.
the film itself is arguably ableist at points in regards to the main character being deaf, played by a hearing woman. some comments in the movie seem off color to me. this is a point of controversy so it's up to interpretation.