Werwolves - lunacy

I began wondering how much of the myth of werewolves is built around explaining mental illness. In older times I can imagine it would be totally baffling as to why someone would be sane acting sometimes, and suddenly have a problem. Now that we know that the human mind is very complex, there are lots of explanations for why things go wrong. But to people who have 'normal' minds, it might have seemed impossible to imagine why their neighbors or family would act strangely.
I found an interesting article on "lunacy."
Please don't mind the comical animated GIF on top.
Lunacy of course coming from the idea that people go crazy when the moon is at certain stages. Even into recent times people believe that a full moon makes people act strangely, though apparently this has not held through testing. If it were true, would it be because people might see the full moon and think they might be allowed to be a little less inhibited?
Another very good article about lunacy.
Could the myth of the werewolf partially be an archaic explanation for the behavior of the mentally ill, developmentally disabled, or alcoholic? Either to soothe the mind of the family, (seems difficult to imagine you'd rather your family member be possessed than afflicted by nature,) or a reason to persecute someone who is not understood by the community.
No one can easily look outside themselves, or imagine what another person's mind is like. People's behavior can seem so strange that they must surely be under some supernatural influence, because, why else would they act that way? I can understand why this sort of thing might be a popular belief.