When the unusual becomes normal.
When the 40 second commute becomes a grind.
When the same view bores you.
When the shave hasn’t happened for a number of days.
When the front door hasn’t been opened.
When the indents in the carpet from the chair become permanent.
Make sure you’ve got people in your network to turn to when you feel this stuff happening. It will and your mental health will thank you if you’ve prepared for it.