There is a large group of SSRI's (Zoloft is one) used for lessening the anxiety in social phobia. The rule of medication is "to go low and go slow" - referring to the dose and the time between increases (if required). I agree with the above poster - maybe another alternative medication might be wise. Could you research this on the internet and take your new-found information to your doctor?
First, have you ever sought out therapy before going to medication? There are many relaxation techniques that might help, and the only cure is to learn to think differently, so have you tried any of that first? Second, Abilify is a drug approved for severe depression that hasn't responded to any other drug. While psychiatrists do sometimes add it to other antidepressants, it would be very odd to add it to a drug when you've never used any drug at all, and it's also odd to add it before you've seen whether the first drug would work without it. Now, if you really need medication because your life can't be lived without it and you've exhausted non-medical help, then Zoloft is a good drug to try, but again, why would your doctor combine it with a second drug without trying first drugs first?