As a point of fact Robert never intentionally hurt Cersei, in the books he even expresses sadness that she never showed any love for him. This cold and loveless relationship is probably what drove him to drink and womanizing in the first place.
Another point is Tommen, even the books glance over him, but it needed to clear that the kid is actually alright and left to his devices would probably end up being a decent king, unfortunately the Game of Thrones is not gentle with kind people.
