Hi Svenson,
Thank you for this input. Until your post, I hadn't heard of Delta Green. I just took a quick peek. Given what you wrote this makes sense to me. In fact the point of getting more experience eroding one's sanity was where my confusion lay. I just thought repeated exposure would eventually tear apart a person's mind, regardless of the mental health help they got. Furthermore, given the mythos is a hidden part of the universe, mental health professionals wouldn't necessarily be exposed to the mythos, and thus treat everyone who's been exposed a sick people. And as a result giving the characters useless treatment.
I'm going to take a deeper look at DG. I really appreciate your perspectives on this question.
Regards,
Mike