Acute suffering should be enough to make us focus on conflicts between our mental subsystems.

I get your point, and I agree. At the moment I believe suffering fails to focus our attention in the right place because evolution hasn't had either the time or the capacity to give us the exact correct instincts.

I vaguely recall an experiment where someone (I don't recall who) made a horse suffer in the sense we're describing here. They trained it to do X when it was shown an ellipse with the vertical direction longer, and do Y when it was shown an ellipse with the horizontal direction longer, and gradually showed it ellipses that were more and more circular, so it had no way to decide which one to do. It did the "brooding and wailing and distraction" you're talking about.