First some SPaG I noticed
Four months ago that had led to a dramatic change in his life.
This is a very awkward sentence, that I'm not sure what it means. My guess is that you're trying to say something happened 4 months ago, which is fine but I think you're missing some words.
That is how he told it to Sam anyway.
Usually anyway would be anyways in this context.
This is a super good, contained short story, I really like it! Personally, I wasn't bothered by the telling and not showing aspect for this story like grendelnacht noted in the discord, I felt it worked for the way this story was presented. However, I do agree with the point that clarifying Sam's inability to leave or function as well as Mary would, and I did see you agree with this, I just wanted to voice my support.
I don't have much else to add other than that, I can't wait until this is posted!