A notable one in "You May Now Kill the Bride", when the victim's husband blames himself for his new wife's death. It becomes very clear through the conversation that Horatio is reliving Marisol's death, and just how deep that particular emotional wound goes.
Horatio: So you believe you're responsible for your wife's death.
Husband: You ever see someone you love die, Lieutenant?
As a matter of fact I have
, Mister Turner.
Husband: Right in front of your eyes?
Husband: When will I get this image out of my mind?