Of course the world is full of make believe Marines. Oddly, people with personality disorders like to claim to have PTSD. They think it is more prestigious than whatever they have. The ones who make up or embellish military service are more eggregious. The bullies among them like to scare people with the implied threat that they are very crazy and very violent and youd better be very submissive and very afraid. But If this guy was doing that you would have checked his story.