The way our mind works, associations need to be strengthened for permanence (which is an extra-weird process because it can apparently modify memories).
More importantly, he needs to get this off his chest. You find people to talk to in the msot unlikely places.
Both language as encoding of thought and transmission are lossy. Rule of thumb: A sentence contains four different things: what I mean, what I say, what you hear and what you understand.
Putting things into words already is an important part of how we for ourselves deal with the incomprehensible, the disturbing and revolting.
Finding agreement, or at least getting feedback form others that our words form a comprehensible sentiment, heck - just knowing that we ended up with a gramatically well-formed sentence comforts us that the abyss between you and me, between you and everyone else can be bridged.
tl;dr: it's great that it can be said.