Hi, im just about to start zoloft (sertraline) after prozac pooped out after 8 yrs, should I be hopeful? Also does it matter starting on 25 or 50mg?

Always be hopeful! If you really can't - don't do it until you can. The best start dose for you is the one your provider feels best about and can explain to you. Your confidence in them will make things go better than having doubts. But do ask! Best wishes.