I take every chance I get to recommend Dark Water (2002). It's a supernatural movie that takes advantage of our inherent fear of drowning, but more importantly, it's about the main character's struggle to hold onto her daughter in the face of the paranormal events she's experiencing, the paranoia they're causing her, and a custody battle with her ex in the aftermath of their divorce. Maybe I was just going through a hard time when I first watched it, but it had me in tears