Warning: Spoilers Off applies to Moments pages. Proceed at your own risk.
Attie's death. After being repeatedly established as a Nice Guy and The Heart of the Teth survivors, it's incredibly depressing to see him die.
It's almost worse to see the heartbroken grieving of all of his squadmates.
Droidbait stops speaking,and is nearly catatonic for several days.
Del blames himself for Attie's death, thinking that if he hadn't been injured it wouldn't have happened.
Coric turns to alcohol to try to make himself feel better. When Domino confronts him, he breaks down, nearly in tears, sobbing that "He always hated it when we drank".
Zeer becomes self-destructive, pushing himself past his limits in sparring. It takes Rex intervening to prevent him from seriously injuring himself.
Jek being killed during an attempt on Padmé's life, while Rhys mourns him and screams that they were going to make it out of the war together.
Echo breaking down in tears after quickly abandoning his brief and ill-thought out attempt on Wat Tambor's life. It turns into a Heartwarming Moment when he's comforted by all of Domino Squad.
Fridge Horror comes into play when you imagine what might have happened if the Force hadn't urged Fives to go check on him.
A Heartwarming example of this comes into play when Fives suddenly meets Kix and Jesse, his old friends, for the first time since he came back.
And then it quickly jumps back to regular tearjerker again when he realizes that they have no idea who he is.
Five's nightmare when he's in the med-bay after the Blue Shadow Virus incident is made entirely of this and pure nightmare fuel.
Kyber... just Kyber.
Wolffe's reaction when he realizes that Fox's chip has been activated, and that he's desperetly Fighting from the Inside. He's clearly trying hard to put on a brave front and not break down. Even worse if you subscribe to the common fan theory that they're batchmates.