Q. So even though I have been living out of my parents IL home, it is not my main primary home, and therefore state of residence, because it is not their primary home?
A. Simple answer: yes.
That said, why do you now say "have been living out of my parents IL home" when earlier you said "January through May I lived in Indiana while at school"? Why do you parents have an apt. in Chicago?
While you were "away at school", and a dependent of your parents, you are considered to be a resident of the same state as them.
