I think it’s a foreign film, maybe Italian.
There’s a college student, and she meets a cute woman at the library. That person shows up outside her dorm that night. It becomes clear that whatever the main character desires starts to come true. At one point she makes her crush disappear, and there’s just a strand of her hair stuck in a glass pane. Toward the end, she sets her abusive Christian dad on fire, while out on a lake in a boat. She gives her mom back the ability to walk after being in a wheelchair. The protagonist’s grandma shares the same power.

Edited question