Player: "Will there be sexual themes?"
DM: "Yes"

Wrong answer DM, the correct answer is "why?" Once they tell you why, then you can say yes or no.

I once had a dude that wanted to play a female that had been repeatedly raped in her backstory, by many men, including family… I was of course appalled, but out of curiosity, I asked if he would consider playing a male character instead, as it may be easier to roleplay (since he was a big burly dude) and immerse ourselves. He agreed to play a male, until I insisted he keep the backstory the same, then he said “that backstory only works with a female character.” At which point I removed him from the game ha ha ha.

Man, Pink needs therapy, not DnD. I mean rpgs can be therapeutic, but no, this girl needs straight up professional help. There's telling people about your trauma, then there's straight up slitting your throat and spraying it all over anyone who is standing in the splash zone

The faster some of these players understand, "just because you can handle it just fine, doesn't mean everyone else can", the better the experience will be.

As someone with a history of trauma (nothing like this tho), I find I make my character have what I didn't have: a loving supportive family, a peaceful upbringing, and good role models.

After hearing the bit that had to make even the mighty crab sit back in his seat and think about life for half a week, there’s only one question I have for this person: “Who hurt you, and do you need medical attention?”

Without dumping my shit: I relate to Pink on a personal level. However, I also think recovery means learning about consent, including other people's. You have to know your audience. Rather than bringing my trauma dump character to group games, I RP her with my significant other (not ERP, just 'hey I'm hurting, are you up to explore this feeling with me?'). My SO does the same. Despite establishing this rapport, we also ask every time, IC or OOC, "Hey, are you mentally solid enough for me to get into this right now?" Sometimes the answer is no and we accept it graciously.

Unfortunately, I can see the miscommunication that happened here. Pink dipped her toe into the pond and waited for DM to react before going further. DM okayed phase one, so she thought it was safe to proceed. She dumped the whole mf. DM only read halfway before going 'uhhh sure' so Pink thought she had consent. Consent can of course be retracted at any time, and DM clearly did not consent to RPing this kind of villain but still, the way this went down, Pink must feel like 'yes' doesn't actually mean 'yes' and feel like an idiot for trusting and opening up to people. I don't think there's a strict Bad Guy in this story, just clashing needs without proper outlets. I agree with OP: I hope she gets what she needs.

idk where these folks live, but as an American, letting the trauma fester unfortunately isn't always our choice. I couldn't get health insurance until I was pushing 30. For 25 years, I begged for some sort of professional help that didn't cost as much as a house, wrote my cries for help into my assignments at school and somehow never got sent to the counselor's office (not that the school counselor would've known wtf to do, but still). I think this is a glimpse into what happens when you put a paywall in front of people getting their shit taken care of.

when i heard "RP trama" I thought like "Get sad around this place, this sword reminds you of your dad" NOT THAT, NOT THAT AT ALL

Saying she was just “whining about her trauma” kind of rubbed me the wrong way, but your other insights were pretty good. It’s clear that Pink needs real professional help in one form or another, and D&D with random strangers on the internet is not the appropriate outlet for her issues. It’s not right or fair to dump trauma on people who have their own problems and who aren’t professionals who have the tools/skills to handle it properly. I hope Pink gets the right kind of help soon.

"Role-playing games are NOT therapy."

-Mage: The Ascension 20th anniversary corebook when explaining what role-playing games are and are not

I dm a curse of strahd game, and my last session ended with: killing and chopping off Izeks arm, had a pp fight amongst 3 players and a monke, tried to find a tavern keepers daughter who didn’t exist, and destroyed a shelf trying to flirt with the shop owner who was a burly bald man, mistaking them for a woman

Gonna fully out myself here but I feel like I need to say this. Sexual DND is fine, with the caveat being that it has to be treated as a real life sexual act in terms of consent. E.g. if you just unzip your pants at the table don't be surprised when you get slapped with indecent exposure. So when you go into a normal dnd game and suddenly try to talk about the details of your hijinks with the bar maid don't be surprised when you make people upset.

You can be furry, weeb, a nympho, whatever. But the only time this becomes an issue is when you fail to properly establish consent, or cross lines in the sand

So, I have a little mental health training with regards to at least identifying the behavior of abused persons, and I would 100% recommend her for review and counseling...

Hypersexuality such as "I seduce every character" is, amongst many other things, one of the possible responses to childhood sexual abuse.
Some might see it as a way to regain ownership over that part of themselves, by embracing it, but it's not exactly a healthy coping mechanism as you can imagine - and can lead to further abuse.
The rest rings pretty true as an attempt to vocalize and objectify their past experiences, by project them onto a characterized fictional version of themselves.
They are, in a way, trying to give themselves therapy, but by forcing their experiences onto people who are neither consenting nor trained to deal with it they're only succeeding in pushing people away who are unable to respond in the way she needs.
Having said that, it's still better that she'd doing this with D&D than actually going out and behaving like this with people in person - but it's also entirely possible she is, or will do that as well. This places her at more risk, physically and mentally, as a vulnerable person especially in regards to mental stress, sexual violence, and addiction.

I do hope she gets treatment.
Perhaps, if actually paired with someone trained, role playing games could even be used as a method of therapy, but that approach is up to the capabilities and diagnosis of her medical provider - which I am not.

Overall a minor thing, but OP sending out a message telling everyone to be adults…which didn’t get responses…yeeeeah, I don’t think that was the right move. They say it was because it was late, but it’s not hard to imagine how that phrasing could rub people the wrong way. Further, it being sent to everyone makes everyone think they might be the one getting called out and/or speculate on who is the focus of that statement.

Not a therapist or psychologist, but trying to recreate the event with expectations of a better outcome is actually one of the responses some survivors experience. You can do so healthily by gathering consent and establishing boundaries, but its not something that should be sprung on the party out of the blue. I see a lot of people saying she should just get therapy, but I'd like to remind everyone that money unfortunately exists. Hope the DM learned to screen players a bit better after this, lol

I dont understand why more DMs dont just set a ground rule along the lines of "this is a roleplaying game for everyone, not your personal smut novel. Sexual RP/backstories/etc are not allowed." Seems like it would nip a lot of these horror stories in the bud.

There's definitely a place for dark and mature themes in D&D, including all the "triggering" topics mentioned here. That's what grim dark is. It's very hard to do properly though. First off, everyone at the table has to know that going in and be ok with everything that entails. Second, not making a self-insert is incredibly important. You have to be able to distance yourself as a player from whatever dark shit is going on with your character.
Pink up there violated all of that, whether she actually was a psycho or not.

Ok, cards on the table here.  I was in a car accident when I was 4.  My family survived, thank God, and the only real injury I suffered was a nasty gash on my elbow that I still have the scar for.  

Naturally, when something like that happens so young in life, you get traumatized by it and I definitely was.  I was afraid to drive until I was almost 17 and even now, I still get a little triggered whenever some idiot almost runs into me on the road.

I bring this up, not for sympathy points, but because I noticed that when I write characters with trauma or tragic backstories, I tend to write them as having been in a car accident.  I realized I was doing it subconsciously and finally consciously noticed the pattern and realized I did it because of my past.  While I still feel it makes for an ok backstory for some, I have tried not to lean on it so much and try to come up with something else.  I feel Pink really needs a lot of therapy to try to work out their issues.

At one point, I was with someone who made Pink's trauma their whole personality, and we happened to have some dnd like roleplay storytelling we did.

For some reason, they really really wanted my character, a cowboy gunslinger who feels righteous indignation to anything he can, to kill someone because for... Well, for giving the trauma related to the person.

This same cowboy gunslinger took a look at a murderous supercomputer and opted to debate with it, mind you. I said he wouldn't, and they chose to just... Make them disappear. Crazy work.

In 30 years of being a DM I have never had to come across a sexual backstory.  Yes, jokes can be made, so long as you remain respectful (my players tease me as much as I tease them) but my session zero is always "Lets keep this PG guys" - and I find almost every single player is happy with that as a compromise.