ANSWER:
All People have gone through some sort of trauma in their lives and came out of it. If everyone of us wants, we can blame our failures and laziness upon such calamities.
Wailing, complaining, pointing fingers and being negative will never change the past nor the present.
Your son needs to go return to Allah and start trusting, depending and relying on Allah alone. Once he does this, he will totally snap out of it and see the world differently. His trauma would become a memory and he will move forward.
Once he understands the importance of the father in Islam, he will forgive his father and start to appreciate him not for who he is but rather for what Allah has ordered him to become; dutiful and respectful.