Please don't list this on a work's page as a trope. Examples can go on the work's YMMV tab.
Tear Jerker: CSI: Miami
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?
Horatio: 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?
Eugene, the mentally disabled man who was beaten to death because he witnessed a murder, and the guy who did it tells Horatio that he did the guy a favour by killing him. Horatio tells the guy that Eugene's DNA was found on his clothes and as a result he will be going to jail for life. He then takes Eugene's body and places his badge on it, saying that he knows Eugene's father would have been proud of him, and that Horatio is grateful to him and proud.