Much of the story in Classic Alice, especially the original plotline, revolves around what happens AFTER college; all the characters seem acutely aware of how difficult life is beyond hallowed halls and both fight against and and struggle to be accepted by adulthood. In book 9, Alice has some tough realizations about kindness vs the world of business that she struggles to marry. Alice's relationship also disintegrates rather than implodes, which is a much more adult way of a relationship ending. Cara encounters her own problems when Ewan outs her, Reagan gets into a car crash and issues about sex, responsibility, and more rise throughout the seasons.
The Anglo/American – Nazi War : Lots of it. It's a detailed analysis of an alternate World War II where the Nazis win at Stalingrad and force a Soviet surrender by 1943, leaving the Nazis free to inflict their murderous vision on Europe until they are defeated again in 1960. Graphic descriptions of Nazi genocide and slavery practices, a total Holocaust, chemical warfare attacks which are launched at Britain and kill off the royal family, a resulting total war which results in practically the wholesale destruction of western Europe, the Hitler Youth being recruited into the SS and becoming Sociopathic Soldiers and suicide bombers, the list just goes on and on.
The Autobiography of Jane Eyre, "Mistake" - Ep. 3: Jane left her mobile phone on the bus, which is a very stressful situation in itself. Moreover, she's on her way to start a new job that she found on Craigslist. She doesn't have a family or close friends, therefore nobody knows where she went. The person who was supposed to give her a lift from the bus stop didn't show up, and she only wrote the contact information in her mobile, so she can't phone them. It's nearly midnight and the bus terminal is in the middle of nowhere with no people around. She beats herself up emotionally for not being cleverer about the whole situation, and she starts suspecting that she's in the wrong place. Then she but half-expects that she will get mugged or worse... There was just time arrival mix-up. It was resolved only in the video description, which makes it all the more disturbing.
Camp Camp: While exchanging spooky stories, Max freaks out Gwen by asking her to contemplate the job market she'll enter once Camp Campbell shuts down.
Near the end of the episode "Mind Freakers" Neil almost asphyxiates Nikki by shoving a bunch of scarves (and a live rabbit!) down her throat. The other kids are horrified by this and don't know what to do as Nikki starts foaming out the mouth as she seemed to be on the verge of death. Meanwhile, David and Gwen are distracted watching Bob Ross on television to notice what is happening.
On Das Sporking, one of the things that sporkers tend to find most upsetting are when authors write characters being "justifiably" abused or write a romance that reads like textbook Domestic Abuse. This is partially because the idea of the author mistreating a character is terrifyingly like watching someone ruin a weaker person's life just because they don't like them, partially because being helpless to stop such behavior is too similar to similar helpless situations with real-life abuse, and partially because it's a horrific reminder that there are people in the world who have such skewed views of justice or romance.
Demo Reel: The root of Donnie DuPre's damage. His mother committed suicide when he was away on a shoot, making him give his worst performance and resulting in years of abuse.
Rebecca was sent away on camping trips with her sexually abusive uncle because her parents just didn't want her around.
Elcenia: In Silver of the Elcenia series, Ehail and Gyre start adopting shren children—essentially, these children have a disability which is very much looked down upon, which is why the children's parents left them. When the disability becomes curable, many parents want their children, and so Ehail and Gyre end up losing their children to their birth-parents.
In The Lizzie Bennet Diaries, a large part of the story revolves around the Bennets' financial troubles and fears of losing their house. After Wickham announces he intends to release a tape of him having sex with Lydia, the sisters have to tell their father about what's been happening. Lizzie's account of it is heartbreaking. They somehow chose not to involve police and it's implied that they can't afford legal action and take it to the court.
Not Always Working has this nerve-wracking story of a new mother who went to the daycare to pick up her infant... only to find the workers locking up for the day, adamant that all children had been picked up already. Not only did they not know where her baby was, they didn't even want to open back up and look for her.
Out With Dad has a couple deal not only with the terror of their teenaged daughter running away, but the knowledge that THEY are the reason why.
Potter Puppet Pals parodies the whole concept of Adult Fear in "Harry's Nightmares", where, nestled in among the bizarre and occasionally juvenile ("In one dream, I was middle aged! Yuck!") traumas that haunt his noggin, was the dream he had where he gave birth to Ron, and raised him from infancy, but one day, he misplaced him, and that terrified him, because it meant he had failed as a parent.
RWBY: In Volume 1, Episode 7, Rubyimpulsively charges at the giant Death Stalker that is chasing Pyrrha. She bounces uselessly off its armour, realises what she's up against and turns to flee. Yang charges towards her, attempting to reach her before the Death Stalker does but an overhead Giant Nevermore launches a feather attack at Ruby. Ruby is pinned to the ground by her cloak and Yang barely escapes impalement by skidding to a stop. Now powerless to intervene, all Yang can do is watch and call out helplessly as the Death Stalker prepares to kill her baby sister right in front of her. Weiss saves Ruby's life by launching an ice attack that freezes the Death Stalker mere inches from Ruby's face but even her magical, speed-enhancing runes barely got her there in time.
Yang tells Blake a moment in her childhood where she and an even younger Ruby left the house when their dad was away, wandering deeper into the woods and arriving at an abandoned house. Only to find it inhabited by Grimm. They would have been eaten if it wasn't for their uncle Qrow coming to rescue them and their father Taiyang would have lost his two young daughters after already losing both his wives.
In the episode "Tipping Point", we see Qrow running in rising panic and desperation to reach Ruby who was being attacked and could have been seriously injured. He barely made it in time and he audibly sighed in relief.
Spoony notes of the Twilight movies that from Charlie's point of view, the story is absolutely horrific. He watches as his daughter comes home bruised and battered, only for her to tell obvious lies and react angrily when he tries to find out what's going on. She ignores him, is constantly deceptive around him, and eventually runs off and marries a guy who Charlie hates for leaving her miserable and mistreating her.
In Vox and King Beau, the titular character Vox gets two: finding out that your partner is cheating on you, and finding out that you have a tumor that could kill you if treatment doesn't go right. Additionally, the "Beau and the Child Snatchers" chapter has a woman who steals children away in the middle of the night and either eats them or turns them into monsters.
The Last Generation is literally built on this. Inna, the main character, is forced to abandon her seven year old blind daughter on her homeworld because she knows that if she doesn't, she will die alongside the entire planet. The fear of not knowing whether her daughter is even alive or has already died alone and terrified stays with her throughout the entire journey. Brought to an extreme when an alternative version of her daughter is burned alive and dies slowly in her arms.
Kell grabs Kyte with a crushing hug after the events of *The Patrol—First Blood: Battle*, where Kytheus, his friends, and a group of legionaries and harpy archers were massively outnumbered in an ambush by the Drex. They win an overwhelming victory, but still..
In the interlude *Mourning Frost*, Lord Frostmourne panics when he notices that his children snuck out to help Kytheus fight the Tyrant.