Want to try a new med.

I want to try another med for my GAD. I'm currently taking mirtazapine (22.5 mg) and celexa (20 mg). The celexa never worked so he added the mirt. then had to reduce it due to mouth sores and my WB count being too low (rare side effect) Now I would like to drop them both and try something else. I just want to take one pill and get stable for a yeart or two and maybe get off of them. How about Effexor? Zoloft? I want to know if I should feel happier than before my breakdown 6 months ago (right now I feel just as unsettled and moody as I did before my breakdown). Any suggestions. I also see a therapist, but she is not very helpful.