I'm really enjoying this show and the characters who are interesting, more than they are likable. As for the comments about Jenny putting down her dog -- I'm only on season 1 and she thinks about it (the dog did bite) but then she gives him to her secretary to care for. I had a hard time with that scene too -- I thought it as callous -- but she was being pressured by her mom and husband.
Not all of the scenes are realistic -- the one where they are all talking about porn put me off. I feel like they try to hard sometimes but if you're a working mom, a lot of the experiences ring true. Wanting to compete but still wanting to be there for your kids; worries about money; postpartum depression and of course the breast feeding wars. My recommendation is to enjoy it for what it is and don't think too much about it.