When it comes to making excuses for playing video games, haven’t these totally worked for you?
“My family is going through a tough time”
This totally works for your boss, right? Family issues stands as a big time iron clad excuse as long as you don’t leave it vague. No one will pry to check if you are depressed, unless the boss is like “I think you should learn to keep your personal life away from professional.” But that would add to his negatives by the other employees.