DevilEyes...exactly. Jack Walsh didn't go nuts when he lost Adam--even though the manner of death surely could've been considered ample cause. Many other people have had horrors happen in their life, even seen it happen right in front of them. Look at people who live in war zones. Yeah, there will be those who come unhinged, but many endure incredible atrocities and come out sane, even though they are scarred.
Yet Dukat DID go nuts. That couldn't have happened without ANYTHING prior there to set up the potential--or at least it would be quite unlikely.