Final answer:
The 20-year-old male's symptoms after witnessing a traumatic event suggest acute stress disorder or PTSD, and professional mental health support is vital for recovery.
Step-by-step explanation:
It appears that the subject of this question revolves around the psychological and emotional responses following a traumatic event. The provided excerpts describe various individuals who experienced significant life changes and the subsequent mental health consequences. In particular, the 20-year-old male who has stopped attending classes and is experiencing extreme anxiety after witnessing the death of a friend is displaying symptoms that may align with acute stress disorder or post-traumatic stress disorder (PTSD). These symptoms can include anxiety, avoidance of reminders of the trauma, mood changes, and disruption of daily activities. It is crucial for individuals experiencing such symptoms to seek professional mental health support to address their condition and find ways to cope and recover from the trauma.