Yes, freewill.

For those with D.I.D., the psyche is what is segmented, not the body nor the soul. For all we know (and I believe He does) God still sees you as "whole" because our concept of time and of space is not what God sees and knows. Just because your thought processes and feelings and memories are divided up for coping doesn't mean that within your own brain/mind you are not whole.

I think it is truly mainly one aspect of any person that surrenders to God and accepts Christ.