The saddest thing you've given your characters to deal with.

Vyomia: being the only one of her kind and completely alone in the void, making her susceptible to its manipulation. When she finally does find people to surround herself with, the void rips it away from her and slowly infects her, making her a prisoner in her own body as the void uses her body as a puppet to harm her friends

Coral (she is kind of a side character now but once was a main character): Coral's childhood was filled with trauma and neglect. Her parents were never around and she was often left in the care of abusive relatives. As a result, she turned to her imagination and stuffed animals for comfort. However, as she got older, her mental health deteriorated, leading her to attempt suicide multiple times. She was eventually admitted to a mental institution, where she has spent most of her teenage years. Despite various treatments and therapies, she still struggles with her mental health and has been discharged and readmitted several times.

Axel: LITERALLY HAS NOBODY. He was born in the void, so he is immortal unless his creator says otherwise. He has no one to talk to, and he's been looking for someone to actually love for about… 3000 years.

Aisha: Being left alone and their friends hating them

Aisha: Plus being born without a dad, they don't know what love is like. It's painful, she doesn't even have emotions, they basically shut them all out.

One of my characters accidentally killed his little brother. It's been over a decade in-story and he still lives with the guilt every single day. He hasn't spoken to his parents or his (now ex) fiancé since the incident because he ran away from everyone after it happened, and he is alone and consumed with regret and self loathing, blaming himself for something that he couldn't prevent or control.

Lottie getting involved in illegal business in order to pay her mother's medical bills, overworking herself to the point of sleep deprivation, and then going on a downward spiral about what her mother would think of her if she knew what kinds of things she was doing.

Monika killed someone under very complicated circumstances, the details of which I haven't hammered out quite yet, but it's a determining factor for how her life goes afterward.

Desdemona meeting the love of her life, only to lose her in WWII.

Aoife getting kicked out at around eighteen years old and living on the streets for a few years.

Rosemary having to get into rather unsavory work in order to pay back the man who paid off her family's debt.

Ramona losing her father at seven years old, followed by her family moving to an entirely different country in the same year.

My Protags Mother being killed by a reincarnated go who is actually his Father, but is also his Son?

My character, Ella fell in love with Loki Laufeyson during their time together on a planet called Sakaar. They both realized how much they had in common and found comfort and solace in confiding their secrets and troubles and trauma to eachother. They had both been through countless horrible experiences that had changed them both into emotionless, hidden people. Ella had to witness Loki be murdered by Thanos and it completely blinded her. She traveled down the path of the Darkhold and she ended up tearing universe upon universe apart trying to find one where Loki didn’t die. Eventually, she found her way to the TVA, where she saw Loki and Sylvie together. She didn’t know that it was the Loki before he had met her and that he wouldn’t even know who she was. She wreaked such havoc on the TVA that she was put in one the highest security prisons that the TVA had, alone, hopeless, forever.

Rainbow diamond had to be stuck on the jungle moon for 1000s of years!

CLAIRE: Claire never met her parents. She never knew what it was like to have a normal childhood. She didn't even know who they were . She always loved to spend time with her aunt and uncle and she enjoyed her life. When she was three, she woke up to screaming in the middle of the night. When Claire got out of bed, she saw Aunt Lindy at the door. Frozen in shock and horror. Her uncle was dead on the floor.
Years later, Claire's now about 15. She and her cabin mates from Camp Moonshadow are looking for something. She finds out that her parents are major people. Not only that but Claire finds out she was lied to her whole life.

CASSIDY: Cassidy is adopted. She never met her parents and they died in a "shooting". Her mother's friend who had witnessed the scene had taken Cassidy. Cassidy was brought to the mortal world and grew up not knowing anything about the wonders of the Celestials. Cassidy was bullied at school for not only being smart but for being both adopted and "Weird". Cassidy's brother wasn't even a good brother. He enjoyed her missery and would ridicule her. When their father would leave and he would watch her, he did horrible things. She was even locked in the basement once. One day when she fell asleep on the couch she was mumbling about war, death, and decay. Her brother overheard and told their father and this whole thing happend.

JAKE: Jake's childhood was an anomoly. In the Realms people rarely had only one parent. Well, that was until 2003. Weird things had started to happen but no one really noticed them. Jake's parents had gotten divorced when he was three, and he and his siblings had lived with his mother, while his father got banished a few years later. Jake was bullied for being the weird one. For having only one parent. Because of all of this he had very low self value and low self esteem.

My big guy has a complicated history of spinal injuries (and reinjuries) that initially delayed the start of his professional hockey career, despite his elite hockey IQ, and led to its premature end like three years later. His only standout NHL season ended in a reinjured back and a strained relationship with his team, resulting in his release soon after their botched playoff run. With contenders and playoff-focused teams giving him a wide berth, his only real bid was on underdog or rebuilding teams willing to gamble on a star-quality player with strong metrics but with an extensive injury record and rumored locker room tension. Which uhh didn't happen anyway, leaving him to recover in solitude with zero offers and no open doors back, soon forgotten in the fast-moving world of pro hockey.

It's somewhat sad for him? Sure, he's alive and well (eventually), but for his kind of 'breed,' it's a failure and a big source of shame and discontent. Cause, despite the odds and an unorthodox path to the pros, he had managed to make it to the big leagues and could have been (and had been for a short time) successful if not, largely, for the decisions he made. He understands that pretty well. His real problem wasn't his physical condition so much as the character he adopted in his most fraught moments. Hubris, hyper-vigilance, and over-control, combined with an intellectual mind that bordered on arrogance at times, shone through, often alienating people around him as a result. And you can't have that in a sport where team bonds are an integral part of sports culture and sometimes are immediately linked to team performance. You also can't have a fucked back and a shitty attitude at the same time, like pick a struggle, man. For a guy with high self-reliance and emotional control, he ironically became more prone to crumbling under pressure when it mattered most. Which, funnily enough, led to him crumbling physically as well in the most important moment of his career. And while circumstances played a role in it all, I'd argue a big chunk of the responsibility still lies with him and his choices.

He's made it work for himself after retiring, though. Slaps his backside How many more problems can I fit into this bad boy

my 3 ocs ran/moved away from 4 different homes, 2 of them were burnt down 1 was a cold storage unit, one of my ocs was severely bullied while the other tried to stop (and also got bullied for it)

The main character for TDFU (My story) delt with denying any love for his whole life (He never got any when he was growing up because the government took his parents away) and when he finally found his first love, a month before they were going to get married, his fiancee died <3
So now he forever denys any love except for the love Scarus gives him. He hates any acts of affection even if its just a compliment but he only accepts Scarus' because in reality he wants to spend his entire life with him. But he know he cannot because he fears anyone he gets close to winds up dead or hurt.

So one of my characters sister got really hurt and now shes paralyzed from the upper waist down and he has to bear that guilt basically his whole life because he could have saved her. They've mostly moved past it but he's still guilty.
Another basically had his wing ripped of so now he has a prosthetic.
Another was tortured in a lab.
Another is deformed from birth and has a ton of things wrong with her.
Uh yeah. My characters are my babies idk about I do this to them. character development

(Important to mention this is a fantasy book) My main character - Aridia - has been through a bunch of brutal training with her best friend - Deanna - (it's a long story) but something happens where Deanna feels Aridia has ultimately betrayed her so they become enemies bc Aridia has 'betrayed her and her whole group and everything they were about'. ANYWAY, in later books Deanna realises all Aridia has sacrificed, and sees all Aridia has gone through to make sure that no one else she loves dies (Aridia has lost a lot of people), and then their relationship starts to build again and when Aridia finally thinks they're okay again, I'm going to rip it all away and Deanna is going to die… And Aridia will blame herself and think that there was something she could have done to save Deanna… Sorry to my readers <3

A terminal illness
Okay so
I have an OC named Coffee Cup who has a disease called TCID (Thermo-Caffeine Instability Disorder) which is hell dangerous bc in my universe, being diagnosed with this is similar to being diagnosed with a blood infection
He used to be a tea cup before, but he fell into the rabbit hole due that his friends pushed him into an addiction what ended on him ODing and getting sent to the emergency room
So he basically became a ticking time bomb :v

The saddest thing I've ever done my character to go through is:

My character lived in a poor, almost neglectful family, but despite the abuse from his stepbrother, his mother helped him as much as she could (since she worked from 5 a.m. to 9 p.m.).
The thing is, in adulthood, when my character is already living a stable life and wants to make his mother proud, she is diagnosed with Alzheimer's, and he has to watch as she gradually forgets everything about the world.

This is practically the story my sister and I lived through, so it's something like a self-insert.

The saddest thing I've ever done my character to go through is:

My character lived in a poor, almost neglectful family, but despite the abuse from his stepbrother, his mother helped him as much as she could (since she worked from 5 a.m. to 9 p.m.).
The thing is, in adulthood, when my character is already living a stable life and wants to make his mother proud, she is diagnosed with Alzheimer's, and he has to watch as she gradually forgets everything about the world.

This is practically the story my sister and I lived through, so it's something like a self-insert.