So, to rephrase what the story's about:Are you exploring a milieu? Not.
Are you exploring a question (idea story)? Not, I think.
Is it a character story? Is MC looking for a new role in life?
Or is it an event story -- something happens to disturb the universe (psychotic break, e.g.)?
According to OSC's Characters & Viewpoint, character stories start with the intent to change role, and end either with the change or the decision to not change.
Event stories start with the disturbance, and end with a new equilibrium.
This might help you decide where the story should start.