How can he be an abomination if he isn't possessed with a demon? I think you seriously are hallucinating, my friend.
You're right, but
according to David Gaider's word
"Regular people can be possessed by demons, and are still dangerous, but they are not abominations. Abominations have access to a mage's full power -- even a weak mage turned into an abomination is dangerous -- while a possessed human (or possessed anything) is only as dangerous as the demon that did the possessing."
Since Hawke is too weak mentally and physically for any demon to gain any power from him, he wouldn't be considered to be an abomination anyway, possessed or not.. 