Im on Zoloft and it works quite well for me, but it took up to 6 weeks to start working properly, so you may have to wait a little while, but it is worth it.
Hang in there and keep us posted,
p.s it DOES get better. it may never be perfect or completely gone, but i swear it does get better. its just hard to see that when you are in the panic pit of despair. also, have you suffered from post natal depression at all?