First of all, the premise of The Other Woman is delightful and I love it. An asshole named Mark cheats on his wife (Kate, played by a hilarious Leslie Mann) with two other women, and the three ladies band together to take him down, becoming best friends in the process. At one point his former girlfriend, Carly (Cameron Diaz), explicitly declares to Kate (and to the audience): “We’re not in competition [with each other].”…