There is no reason you can't take Abilify with Zoloft. I take Abilify with several other medications. It started working within 2 weeks and my depression decreased dramatically. One common side effect of Abilify is akathisia, a restless need to move. I have that but added propranolol and it stopped it completely with no other side effects.
I was originally DX with major depression/anxiety. Also have ADHD. Meds were Zoloft, Adderall. Had two major depressive episodes on that combo. Abilify 5mg was added and the sun came out. Was later DX with BPII. ALSO, after 8 yrs on Abilify, had unexplained weight gain of 15-20 lbs. in spite of good diet, reg exercise. Now weaning off Abilify due to wt. gain and titrating up on Lamictal for obvious mood swings. Idk, Abilify worked well for me with Zoloft for approx 8 years. Good luck to you!