Even though there is such a thing as a 'placebo effect'...I don't really think it could be accountable to the effects that you are experiencing - especially due to the severity of your illness.

Abilify is a reasonably new medication and is quickly becoming one of the favourites for the treatment of bipolar disorder due to its less severe side effects and efficacy in reducing the severity of both mania and depression.

I'd say that you have found the right medication for you (for now at least) as it's been very successful in helping you to 1. Stay out of dangerous mania and depression and eventually 2. Lead a successful and relatively normal life.

Just remember to keep an eye out for decreasing effectiveness and the return of suicidal thoughts and/or behaviours.

Well done and keep it up
RB♥