Attached are my detailed notes as usual.

Solid chapter four! It's great to see the other characters developed more in this chapter. I also think that giving Michelle a base of operations, though only temporarily, was a good move. It was nice to see her somewhere besides wondering through the frozen woods. Again the movement from present to flashback works seemlessly and doesn't interupt the flow of what is taking place in the present. It is also good to see Michelle interact more closely with other characters besides her own psyche.

This chapter reads rather quickly for how long it is. Which is good. You keep the pace and flow smooth that one gets to the end without it feeling like it took too long. I also like how you make steps to prepare for the ending in this chapter so all you have to do is execute it in the final chapter.

Some overall notes I had are mostly around Rita and Ame's dialect. In part three you have Rita speakig in a dialect and in part four  the first sentence is spoken with perfect English. Be sure to keep your characterization continuity. In some sections however their dialect is quite thick and borders on being difficult to piece together and a little unnatural sounding when read aloud. Dialect is a great tool to give characters a rich backstory and flavor but too much and it is hard to read and can approach being unrealistic. I'd go back an smooth it out just a little bit to improve readability. You want to balance the richness of the characterization with the reader's ability to understand what the character is saying.  That was the biggest thing that stuck out to me.

Overall I think you have a great part four to your story!