Morgansangel, your withdrawal from venlafaxine is very different than your being able to stop so-called drugs of reward, like nicotine and codeine. Those act by a very different "addiction" mechanism in the brain. (It is great you have not had problems with those--I am the same way, just not prone to addiction.)

Your withdrawl from venlafaxine is not related to addiction. Unfortunately, it is one of the hardest psych meds to come off on. Are you tapering off venlafaxine with the help of a psychiatrist? One strategy sometimes used is to substitute (gradually) fluoxetine for venlafaxine. This can help alleviate the withdrawal symptoms. Then when you are just on fluoxetine, you can taper that off, which you have done successfully before.

As a point of comparison with your taper schedule: a psychiatrist I know tapers venlafaxine off by 10% per month.

Sorry this is so difficult. Good luck and hang in there.