At first they thought someone was gaslighting her. Once they knew it was her, she sought treatment.
There's no mystery here. Finn is drinking and refuses to stop or go to a meeting or seek help some other way. His family and friends and loved ones and co-workers have tried talking to him, reasoning with him, pleading with him, calling him out, they've tried it all. He responds with anger and denial every single time to every approach. So whatever it takes to keep patients safe from him right now, do it. Wish there was a way to keep Violet safe from him but he's her father with sole custody so that poor kid is doomed to suffer the consequences of his drinking and probably soon.
