i feel for you ive been there its awful when you end up hating work.
my advice to you is if the job aint in the field you want to be in then get out. if it is then try and move somewhere else within the business/industry.

if its not what you want to do anyway dont stick it out it aint worth it. i think once a job effects you negativley when you are away from it then maybe that line has been crossed?

hope you get it sorted either way.