I know depression usually has a grave cause and astronauts have quite an active schedule. But say their family dies. Depression makes you think and perceive time differently. Surely wouldn’t it become a risk to the mission? You can’t steamroll over it…
Depression isn’t the same thing as sadness, and I wouldn’t be surprised if it disqualifies someone from being an astronaut. Most people don’t have depression, but everyone feels sadness at some point in their lives.
To answer your question, astronauts are trained to work under extreme stress, so they would know how to compartmentalize the pain and focus on completing the mission. Similar to soldiers.