Sinful Bastards: Fucking Damn It
The Sinful Bastards campaign started out with the party's hometown being razed, with the children being kidnapped and the rest of the citizenry murdered. My ranger's two sons were taken, so (once sober enough to do so) he vowed to find them.
And he did find them! Moments before they were murdered. Both times during sessions I couldn't attend. This leaves a pretty bad taste in my mouth, because I had spent months realtime preparing for this possibility, and couldn't even take proper vengeance. But as the DM pointed out, these events were scripted, and it wasn't fair to ask him to halt an entire session halfway through just because I wasn't there.
Some time later, we are able to rescue (some of) a third group of children. We bring them back to the nearest city, where almost all of them are quickly adopted, leaving only one child - a half orc - without a new family. I choose to adopt him myself, name him Evvan, and bring him home with me.
The holidays start picking up at this point, and my job leaves me with no time to play, so I temporarily drop out. One day, the DM's girlfriend shows up while I'm working, and we chat about what's been happening in the game since I got pulled away.
GF: "Oh and, uh... I think [DM] killed your characters."
Me: "What!?"
GF: "Yeah..."
I whip out my phone and open the group chat.
Me: "[DM], did you kill Ed and Evvan!?"
DM: "You'd be surprised by what can happen!"
Me: "Seriously!?"
DM: "Muwahahaha!"
Weeks later, my schedule is finally stable enough that I can play again, and I immediate confront the DM.
Me: "Are Ed and Evvan really dead!?"
DM: "I told you so!"
Me: "No, you gave me vague responses and evil laughter! I can't believe you killed my son again!"
DM: "At least Ed is with his family now!"