I used Zoloft for years.  It worked wonderfully well for me, but it stopped being effective.  I was up to 150mgs a day.  I became depressed again.  Cried all the time, could not sleep.  Had no energy.  Thought about suicide.  All the reasons why I went on Zoloft in the first place.  My doctor has switched me to Cymbalta.  While I was going off the Zoloft, taking the Cymbalta at the same time, I was doing much better.  Now that the Zoloft is gone, I am depressed, crying, angry.  The only good thing going on is that I am finally sleeping.  I just don't think I'm ever going to have a normal life.  Maybe you weren't getting enough Zoloft.  I took it for about 7 years.  I would still be taking it if it was effective for me.