Movies are so screwed when the actual actress sounds like she just smoked a bag of weed. Or drank a bottle of tequila. Now i am not surprised playing a drunk was so easy.
The whole idea of a poison taking 3 days to kill a dog is the reason I'm not going to watch this movie. If the writer can't be fucked to come up with something better than that to motivate a protagonist, that writer should quit while she's behind.