Ok well if it's not social anxiety it probably is the withdrawal and you have to let him work through it but be supportive and available so he know you're there for him in whatever role he needs. I know it's hard to deal with but most of these psych meds were only approved for short term use so a lot of people do get to a point where they are either no longer effective or desirable for whatever reason. It's better to taper off the meds but it's too late for that now...the best you can do is wait it out....send him a text every now and then to make sure he knows you're there to help...