@Onsokumaru
You don't seem to understand how trauma works. You can't just reason it away.
1: Just because its traumatic it does not mean that his actions are reasonable.
2: You would need to prove that said past instance was as traumatic as you suggest. So goodluck lol.
3: If your assertion is that he can do and believe anything simply because of trauma, than sadly you dont have an argument. Lets assume that someone has had a traumatic experience with women. For example an abusive mother. Does this give said person the right to hurt any women that they see? Even if his justifications is trauma? No it doesn't. If said person claims mental illness and it works, said person will still be facing something such as medical rehabilitation for his trauma. They dont go free.
You're adamant that Jin is being reasonable with his disdain towards animals. If thats the case than back up your assertion that his trauma was to such a degree. Likewise defend your position on how his trauma and mental illness can get someone scot free.