I'm concerned about this too. I'm already on a trio of medications to treat my major depression. After over a decade grappling with depression, I finally have a handle on it. Due to the success of my drug therapy, I think I could handle the life-change of quitting better than I ever have in the past. 2008 was a rough year for my family and me, with huge crisis after huge crisis. Prior to this combination of meds, I would not have been able to take hit after hit after hit, and remained standing. I'd have slipped into a deep depression and stopped functioning.
So I've rolled with the punches through several major life changes in the past year: daughter moving out, son starting kindergarten, cutting my work hours down to part time, the death of a pet, and major financial problems. I can't believe I'm not curled up in a ball, sleeping 18 hours a day. That's a testiment to the effectiveness of this regime I'm on. Quitting should be easier for me this time (I've yet to set a date); not much easier, but not as horrific as the last couple of times.