I'll add that if you dig deeper, it can explain why people become thrill seekers and even heros or remain stuck repeating bad behaviors.
If it was a life threatening trauma which caused the disassociation, you may only feel alive when in mortal danger. So essentially, one can be programmed to seek out the exact trauma they experienced because in a perverse way it is the only way to feel emotion.
The brain is an extremely misunderstood and complex organ as shown in this PBS documentary.