I took Zoloft for a time - I had some stomach upset and felt slightly "strange headed" (these meds work in the central nervous system so it is understandable one would have some side effects related to the brain) but never dizzy. True vertigo (where one feels like they are standing still and the room is spinning 'round them) is caused by an inner ear problem and frequently associated with nausea.

Hope you have neither issue but if you do, then maybe it wasn't meant to be. Commitment to counseling and a support group are what got me better, not meds.