Are cheswick and Michael maybe the same person or maybe there is two souls in one body

I dont think they're the same person...remember when FL when back in time and she was in the body od the blonde maid? in that time, she meet Cheswick and Michael and they were like the moon and sun (they're two different people)
So ig either Michael die somehow and is using Cheswick body like the ghost lady or they really are two souls in one body...either way, is so confusing(￣∇￣")