It’s about both in a way, her grief turned to hatred of her own child so much so that it developed into her hating regretting and despising her child because he’s all that is left after the loss of her husband, this is why the kid appears extra annoying to us it’s because we see what she sees. At the end she realizes that it’s apart of her for she’ll always miss her husband so she feeds it and keeps it at bay and controls her hate and anger and sadness. Very impactful and beautiful film tbh.