Most psychologist will tell you that when you mind is going dark to change your mindset by concentrating on something different.
You can do this by organizing activities with friends and family. Laughing and spending time with your loved ones can be a good way to distract yourself on a bad day.
You can also build an emergency kit. In it you can put a stress ball, little puzzle games, PlayDoh, positive quotes, sketch book, stuff animals, etc.