What's wrong with the Solo kid?
Star Wars: The Force Awakens villain Kylo Ren is insecure, conflicted, and temperamental. Although a grown man, he throws destructive temper tantrums. Many mental health practitioners like Adam Smith (The Cantina Cast episode 115) suggest that he may have borderline personality disorder, that unable collection of traits defined by poorly formed personality with erratic, unstable traits. A strong argument can be made there. His volatile moods and vacillating views toward important figures in his life (e.g., having both idolized and despised his father) certainly fit. He's a bit old to be acting like a moody adolescent. Could he be a psychopath? The first problem with suggesting that he has any kind of personality disorder is that we don't know what he was like before he got hooked on Force power. Pumped up on the dark side, he may act differently than he did before.
The family dynamics are those of parents struggling to deal with a child whom they still love but who has sunken deep into addiction. His grandfather Anakin was a good, empathetic boy who cared about others and sought to do what was right - the kind of person who does not grow up become a psychopathic mass murderer. I had a hard time connecting Star Wars Episode I: The Phantom Menace's child Anakin Skywalker with the young man he turned out to be in II: Attack of the Clones and III: Revenge of the Sith. In fact, I could do little more than chalk it up to poor characterization until I compared it to drug addiction.
Force power that can lift a spaceship from a swamp or convince a Stormtrooper he's looking for other droids could potentially alter the Force-user's cognitive and emotional processes much like stress, drugs, brain injury....
....may maintain self-control no better than does a person who says, "I'm not drunk," while staggering from having nine drinks too many. "'Roid rage" would barely light a candle compared with the firestorm that dark side-fueled fury might unleash.
(Star Wars Psychology: Dark Side of the Mind, p. 11)
Here's an example of recent Twitter chatter on the subject: