Is DO HYUN SOO a Psychopath?

I was hopping on the Alexithymia Theory Train too until episode 10 came out. SPOILERS IF YOU HAVENT SEEN EP 10.

 As I said I thought he had the mental illness but then during the course of episode 10 especially Jiwon's phone call to Hyunsu, I think Hyunsu is a normal person but raised in circumstances that made him who he is now. The turning point of events that led him to the mental institution (idk how to call it, hospital?) was the death/disappearance of his mother. But as to what Jiwon has said, a normal child would do the exact same thing that Hyunsu did(be violent) when someone touches something that's really personal to him which is the casette tape (his mother's voice). The reason why I'm also putting emphasis on this it's because it was justified as what a normal kid would do when Jiwon and Hyunsu were called by Eunha's school because their daughter touched the other girl's doll and gained a nosebleed from it.

After being misdiagnosed by the Psychiatrist because she didn't look into Hyunsu's condition further, plus the villagers with their gossips and straining looks, probably being labeled as an outcast in school as well, has led him to believe that he is indeed not what you can consider "normal" in the head.

With those in mind, I think what he actually has is Psychological Trauma that, with no help(his father died, sister away), developed further(maybe to the point that he now has Alexithymia or maybe not) intosomething that led him believe that he doesn't feel a thing. 

Until Jiwon came into his life.

@sinistercat yes I have the same thought when I watched episode 10. One of the possible causes of Alexithymia is childhood trauma and/or abuse. DHS experiences his trauma when his mother was missing (childhood) and when the villagers perform something weird to him (adolescence), I forgot what they call it ist it an exorcism? The trauma and abuse that he experiences persist from childhood and even to adulthood which came from the stigma that he is a murderer. 

It is not always good that some mental health practitioners focus more on what is abnormal to treat an individual with psychological and mental health problems. Alexithymia is not a diagnosis or psychological/mental disorder, it is a personality trait. But people with this trait also seek professional help to learn and to be more aware of themselves. 

We can dig deeper about DHS because in the preview for the 11th episode we saw that DHS is crying while driving which is very unusual and good progress for people with Alexithymia. 

Hi, I don't really know much about Alexithymia , but you guys could be right. But so far, I think, his portrayal of ASPD is accurate (sorry, if I am wrong, I'm a not a professional, this is just my opinion).

So, here's my little research before episode 9 and 10 aired, so I wrote this and posted it in a forum after watching episode 8.

• "Antisocial personality (ASPD) is one of the cluster B personality disorders, which typically involve emotional, impulsive, or dramatic thoughts and actions."
• Most people diagnosed with ASPD are unable to feel remorse or guilt.
• They may lack empathy and struggle to understand emotions of other people. 
• They have a tendency towards "impulsive and often dangerous or illegal actions."
• But, NOT every person with ASPD will be a murderer or will commit extremely violent acts. As you can observe with Hyun Soo, he didn't actively engage in violent acts as an adult but only when he was triggered (in the basement scene with Moo Jin). When he was a teenager he tend to took revenge on people who harmed him first, but we never see him initiate the attack.
• It is also possible that they may change (I'm not sure to what extent) as they receive therapy. In Hyun Soo's case, he doesn't have a professional therapist but the way Ji Won constantly pursued him in the past with so much kindness and love might have changed him a little bit, and now, they are living peacefully for 14 years with a daughter, so just like what Hae Soo said, he did change. He just can't distinguish that.
• The stigma is real for people with ASPD. Many people think they are manipulative and would not feel love over their families (they may love their family but  may care less about others, but this doesn't mean they would commit violent acts over others). This is true to Hyun Soo's obsession with the tape (which we can assumed has his deceased mother's humming), the way he protected his sister (tho, he didn't realize it was because he extremely cared for her), when he kissed back Ji Won on flashbacks, when he took care of Eun Ha and has always been considerate of Ji Won. 
• "Research also indicates antisocial behavior may persist longer in men." This might mean that they can absolutely change.
• "Parental neglect, abuse, or inconsistency and a lack of stability from primary caregivers can all increase the risk that a child with conduct disorder will develop ASPD."

Here's my source: https://www.goodtherapy.org/blog/understanding-antisocial-personality-the-stigma-tied-to-aspd-0510197 

Also, by reading this account written by a 31-year old man diagnosed with ASPD and currently receiving therapy, I think, it really fits Hyun Soo's story: https://www.mind.org.uk/information-support/your-stories/life-with-antisocial-personality-disorder-aspd/  Actually, reading this feels like I'm reading Hyun Soo's mind.

As you see, I don't really want it to be a misdiagnosis since I've read that there is a big stigma going around people with ASPD. But whatever Hyun Soo's mental diagnosis, it will be alright with me.

Sigh.

I hope we can have a psychiatrist with us. 

 Darochacamila:

i just want to state that those are similar diagnosis that often changes by the time a personality is being developed. It’s not unusual to see them changed over time or even different psychiatrists not agreeing in a patient’s diagnosis.

True, DHS was diagnosed when he was still young and there is no follow up treatment or even assessment on how his personality progressed throughout the developmental stages (from childhood to adulthood). He's stigmatized as a murderer, abnormal and psychopath. A similar diagnosis can happen to children as the criteria for bipolar personality disorder, conduct disorder, oppositional defiant disorder, and ASPD can overlap.