Courtney Cox has never been a very good actress, but she is incredibly bad in this. Although it's not entirely her fault, since the writing is also bad.
The comedic element is based mostly around the fact that Pat (Cox) is a bad mom and a selfish person. This gets old quick. She's constantly talking about how much she hates her kids, especially her daughter, and it's really weird. It's clearly meant to be edgy and different but ends up just feeling sloppy, lazy and frankly a little icky. It's trying so hard to be like the Santa Clarita diet and failing miserably. If you haven't seen that, you should. It's an excellent example of how an idea like this one can be done right.