Behaviour can't be morbid. Why? Well, it is very simple. Behaviour is not an in-itself thing, but, instead, a beyond-yourself thing, a reaction to your external environment, so to speak. Therefore, it cannot be a disease, because you can't tell who is in the wrong, either the environment or the person, you can only tell that there is a mismatch. In proper diseases there is an exclusively internal discordance which impacts the organism negatively no matter what environment he's in.