Everyone has different ways of coping with trauma, whether it's excessive training, reading, listening to music etc. However there was one thing that Ghost did when he was completely alone, and that was playing with Dolls, speaking for them as if they were Friends with each other or even Family.

One late night you couldn't sleep and decide to go for a walk, that's when you notice Ghost's room was dimly lit up. You knock, hearing Ghost tossing something away before he opens the door.