Hi madhattr88.
I'm sorry you are going through this. What nobody explains to those of us taking antidepressants for years is that we develop a tolerance to them, and though we may be going along fine while this is happening, a big stressor or change, like quitting smoking (plus nicotine affects acetylcholine and its receptors) can trigger tolerance withdrawal to manifest itself with depression and anxiety being symptoms, not relapse. How is your sleep? Often insomnia will begin under these conditions as well.
Doctors usually respond with an increase in dosage (to overcome tolerance) but this may not help or won't help for long before tolerance sets in again. The other response is that doctors will switch us to another AD, but then you will REALLY have withdrawal from the first drug for which the new one may not cover completely.
What really is best is to come off the med. Typical of many of us long term users, you kept taking the drug past when it had helped you. These meds were never proven safe beyond 6-8 weeks before going to market, and now the writing is on the wall: long term use causes treatment resistant depression, studies have shown.
You are wise to taper off the klonopin, as benzos are a whole other ball of wax as far as dependency is concerned; just two weeks of daily use can cause it. You should not taper two drugs at once. How are you coming off? Were you using it daily and if so how long?
I will caution you that you are at risk of being labelled biopolar at this point, a very common sequellae to mis-diagnosed tolerance WD. Bi-polar has become epidemic as the number of long term AD users rises; it is caused by the drugs and is not a real condition to be medicated with additional meds.
I also have a family history of depression, with many relatives medicated. However there has never been a disease process identified for depression, no imbalance that the drugs treat. In my family's case it is more likely poor coping passed from generation to generation. Cognitive behavior therapy and meditation/mindfulness have been proven to be more helpful than medication, without the side effects and risks. We can learn how to cope with stress in a healthier way.
So, the good news is that tapering off of Zoloft slowly will lead you to feeling better, not worse. You didn't need meds until childbirth, right? That was chemical upset, not YOU. The meds are likely your probelm now, not YOU.
I'm going to send you a link that will hopefully clarify things for you even more.