80mgs is the maximum U.S. maintenance dose but if you need that high a dose perhaps your doctor could lower your dosage with an add-on...I did well on 40mg with Abilify 20mg.
Also, different people respond to every medication differently and maybe this just isn't the right one for you. There are many options to choose from...a different SSRI, an SNRI, an atypical like Wellbutrin...?