Death in game: Does life go on or do you revive your sims?

I roll back emotional deaths without a qualm.

I've had some sims die due to accidental death. If it's the sim I am currently playing, and I usually play single sim household, then I just exit without saving. If it's a multiple sims households I will continue playing that session and try revive them, if not able to revive them by the time I am done playing, then I just exit without saving. It's it's random townies then I will keep their urn with intent to revive them at a later time, but I usually never get round to it. Haven't played much since Life and Death EP and no deaths so haven't played through the afterlife yet, might be tempting to play with single sim households if they pass away accidentally. My sims tend to live forever. 

I usually welcome death in my game
because there is so many sims I want to play and so little time, and Grims a pal really.
(Can't deny I also kind of love being macabre about it, for some reason it just tickles my spooky braincells)

but when it is favourite sim I would suggest trying to revive them in gameplay, think ambrosia is base game too 🤔
or play them as a ghost until everyone is ready to move on 😊

Modded out emotional deaths.. no thanks for those. 

Other than that.. depends on sim.. and the way the death happened. Some may fit the story more I thought.

I used to play aging off, but did not like that either.. so now my sims have very long life, but not immortal. (aging on long ans only on for all , every first week of spring and fall, 28 day seasons)

Rip to your sim
I’m very careful with their needs and emotions to avoid any accidental deaths but if it happens mostly I accept it and continue. Only because if it managed to slip past me, it was meant to be. 
On very rare occasions I rollback, and it’s only when I feel like how you said it, “feel this sim’s life was robbed before their eyes”. 

How you describe it, I think it would be best to roll back a save. This sim seems to be important to you and you seem to have plans for them. I decide from case to case. Sometimes I just accept what happened and go on with it. For example: I had a happy couple and he died of electrocution. After she finished grieving, she moved to a different world and got to know somebody else. But sometimes when the sim ist very important to me or I have plans for that sim, I roll back a save. 

I think I've only rolled back a save once and that was because my bride died of laughter right in the middle of her wedding. 😅 I hate losing progress more than I hate unexpected death but I also LOVE ghosts. I have a lot of playable ghosts in my game and one of my favorite packs is Life & Death. I love the ghost powers and the rebirth thing, so I usually embrace the ghosts because I tend to roll with the randomness of events in my games. There's always ambrosia if you want to make them alive again (you can download a readymade one from the gallery). I've done that on occasion, but I usually keep the ghosts and continue the story from there. Some Sims are hard to let go of so that's why I like to keep them around after death. Especially pets. I have so many pet ghosts! 😁Right now one of my Sims is getting all his riding trophies on a ghost horse. 

For me it depends on the circumstances and the sim's point in life. For someone just aging to young adult, I would exit without saving in most cases. I have let them go when they were adults and not too far from elder stage, kids all grown up, etc. Plus, it does feel like it wasn't meant to be in your case since they had gotten rid of the hysterical emotion.