I’m afraid the article you linked also says anger can be a primary emotion or a secondary emotion.

Is anger always a secondary emotion?
It makes sense to feel angry as a response to injustices, perceived threats, or frustrations, and anger might truly be your primary emotion in the moment. It isn’t always masking another, more vulnerable emotion. For example, if an acquaintance made an inappropriate, derogatory comment about you in front of others, you might immediately be angry that someone unjustly crossed a boundary. In this case, anger is still functioning to alert you to something getting in the way of your goal (e.g., of respect), plus it’s an immediate, instinctual response to the situation.

Tbh I’m not a big fan of the article. It does not match up very well with my understanding of the emotions.
For example, Anger is a problem-solving emotion. Fear is the defensive emotion. Yet the article seems to mix up the two.

How do people willingly confront their most traumatic experience again and again?

I’m not entirely clear if this is a rhetorical question and you wanted to vent for a bit, or if you’re genuinely looking for an answer?

If it’s to vent, then I kinda understand. It sucks to see someone you love suffer. It sucks again when you think you found an answer and they tell you no. Each time you try again and get your answer rejected, the feeling gets worse and worse until you start blaming them for their own suffering. I’ve been on both sides of that.

They tell you to stay strong. That love and patience will change their minds eventually. On a level, it makes sense. If a problem has been persisting for decades, it’s kinda unfair to think you can solve it overnight. It’s likely the solution is also going to take years. But then you spend the time trying only to find more layers to the problem.

If you’re looking for some kind of answer, then the best I can offer is it’s Trauma. We all go through our own traumatic experiences. Events so bad it takes away a piece of us and leaves us scarred. Those scars change how we each approach or avoid situations. Not many people want to relive their traumatic experiences, even if it would lead to better lives.
Sorry if it’s not the answer you’re looking for.

There’s a modified Chinese proverb I like that goes something like this:
Watch your emotions, for they become your thoughts.
Watch your thoughts, for they become your words.
Watch your words, for they become your actions.
Watch your actions, for they become your habits.
Watch your habits, for they become your destiny.

Basically the takeaway is that your emotions/attitude aren’t the end point, they’re the start point. The pattern in your comments keep reading of Self-Loathing. That emotion is forming itself into your thoughts and words. Anger management techniques are critical to controlling this metaphorical “curse” you’re under.

Thank you to Dan Soza. It’s always good to know there are people that care so deeply about protecting the vulnerable. The fact there are so many sane individuals out there, like Soza and fellow lemmings in this thread, pushing back against the delusion brings a comfort to my soul.